Python django.utils.six.itervalues() Examples

def allow_lazy(func, *resultclasses):
    """
    A decorator that allows a function to be called with one or more lazy
    arguments. If none of the args are lazy, the function is evaluated
    immediately, otherwise a __proxy__ is returned that will evaluate the
    function when needed.
    """
    lazy_func = lazy(func, *resultclasses)

    @wraps(func)
    def wrapper(*args, **kwargs):
        for arg in list(args) + list(six.itervalues(kwargs)):
            if isinstance(arg, Promise):
                break
        else:
            return func(*args, **kwargs)
        return lazy_func(*args, **kwargs)
    return wrapper 

def keep_lazy(*resultclasses):
    """
    A decorator that allows a function to be called with one or more lazy
    arguments. If none of the args are lazy, the function is evaluated
    immediately, otherwise a __proxy__ is returned that will evaluate the
    function when needed.
    """
    if not resultclasses:
        raise TypeError("You must pass at least one argument to keep_lazy().")

    def decorator(func):
        lazy_func = lazy(func, *resultclasses)

        @wraps(func)
        def wrapper(*args, **kwargs):
            for arg in list(args) + list(six.itervalues(kwargs)):
                if isinstance(arg, Promise):
                    break
            else:
                return func(*args, **kwargs)
            return lazy_func(*args, **kwargs)
        return wrapper
    return decorator 

def keep_lazy(*resultclasses):
    """
    A decorator that allows a function to be called with one or more lazy
    arguments. If none of the args are lazy, the function is evaluated
    immediately, otherwise a __proxy__ is returned that will evaluate the
    function when needed.
    """
    if not resultclasses:
        raise TypeError("You must pass at least one argument to keep_lazy().")

    def decorator(func):
        lazy_func = lazy(func, *resultclasses)

        @wraps(func)
        def wrapper(*args, **kwargs):
            for arg in list(args) + list(six.itervalues(kwargs)):
                if isinstance(arg, Promise):
                    break
            else:
                return func(*args, **kwargs)
            return lazy_func(*args, **kwargs)
        return wrapper
    return decorator 

def allow_lazy(func, *resultclasses):
    """
    A decorator that allows a function to be called with one or more lazy
    arguments. If none of the args are lazy, the function is evaluated
    immediately, otherwise a __proxy__ is returned that will evaluate the
    function when needed.
    """
    @wraps(func)
    def wrapper(*args, **kwargs):
        for arg in list(args) + list(six.itervalues(kwargs)):
            if isinstance(arg, Promise):
                break
        else:
            return func(*args, **kwargs)
        return lazy(func, *resultclasses)(*args, **kwargs)
    return wrapper 

def _prepare(self, model):
        if self.order_with_respect_to:
            # The app registry will not be ready at this point, so we cannot
            # use get_field().
            query = self.order_with_respect_to
            try:
                self.order_with_respect_to = next(
                    f for f in self._get_fields(reverse=False)
                    if f.name == query or f.attname == query
                )
            except StopIteration:
                raise FieldDoesNotExist('%s has no field named %r' % (self.object_name, query))

            self.ordering = ('_order',)
            if not any(isinstance(field, OrderWrt) for field in model._meta.local_fields):
                model.add_to_class('_order', OrderWrt())
        else:
            self.order_with_respect_to = None

        if self.pk is None:
            if self.parents:
                # Promote the first parent link in lieu of adding yet another
                # field.
                field = next(six.itervalues(self.parents))
                # Look for a local field with the same name as the
                # first parent link. If a local field has already been
                # created, use it instead of promoting the parent
                already_created = [fld for fld in self.local_fields if fld.name == field.name]
                if already_created:
                    field = already_created[0]
                field.primary_key = True
                self.setup_pk(field)
            else:
                auto = AutoField(verbose_name='ID', primary_key=True,
                        auto_created=True)
                model.add_to_class('id', auto) 

def get_node_ip_by_nictag(self, nictag, node_nics=None):
        """Return node IP address according to NIC name (nictag)"""
        if node_nics is None:
            node_nics = self.used_nics

        for nic in six.itervalues(node_nics):
            if nictag in nic.get('NIC Names', ()):
                return nic['ip4addr']

        return None 

def list(self, ignore_patterns):
        """
        List all files in all theme storages.
        """
        for storage in six.itervalues(self.storages):
            if storage.exists(''):  # check if storage location exists
                for path in utils.get_files(storage, ignore_patterns):
                    yield path, storage 

def get_action_choices(self, request, default_choices=BLANK_CHOICE_DASH):
        """
        Return a list of choices for use in a form object.  Each choice is a
        tuple (name, description).
        """
        choices = [] + default_choices
        for func, name, description in six.itervalues(self.get_actions(request)):
            choice = (name, description % model_format_dict(self.opts))
            choices.append(choice)
        return choices 

def _prepare(self, model):
        if self.order_with_respect_to:
            # The app registry will not be ready at this point, so we cannot
            # use get_field().
            query = self.order_with_respect_to
            try:
                self.order_with_respect_to = next(
                    f for f in self._get_fields(reverse=False)
                    if f.name == query or f.attname == query
                )
            except StopIteration:
                raise FieldDoesNotExist("%s has no field named '%s'" % (self.object_name, query))

            self.ordering = ('_order',)
            if not any(isinstance(field, OrderWrt) for field in model._meta.local_fields):
                model.add_to_class('_order', OrderWrt())
        else:
            self.order_with_respect_to = None

        if self.pk is None:
            if self.parents:
                # Promote the first parent link in lieu of adding yet another
                # field.
                field = next(six.itervalues(self.parents))
                # Look for a local field with the same name as the
                # first parent link. If a local field has already been
                # created, use it instead of promoting the parent
                already_created = [fld for fld in self.local_fields if fld.name == field.name]
                if already_created:
                    field = already_created[0]
                field.primary_key = True
                self.setup_pk(field)
                if not field.remote_field.parent_link:
                    warnings.warn(
                        'Add parent_link=True to %s as an implicit link is '
                        'deprecated.' % field, RemovedInDjango20Warning
                    )
            else:
                auto = AutoField(verbose_name='ID', primary_key=True, auto_created=True)
                model.add_to_class('id', auto) 

def list(self, ignore_patterns):
        """
        List all files in all app storages.
        """
        for storage in six.itervalues(self.storages):
            if storage.exists(''):  # check if storage location exists
                for path in utils.get_files(storage, ignore_patterns):
                    yield path, storage 

def get_action_choices(self, request, default_choices=BLANK_CHOICE_DASH):
        """
        Return a list of choices for use in a form object.  Each choice is a
        tuple (name, description).
        """
        choices = [] + default_choices
        for func, name, description in six.itervalues(self.get_actions(request)):
            choice = (name, description % model_format_dict(self.opts))
            choices.append(choice)
        return choices 

def _prepare(self, model):
        if self.order_with_respect_to:
            # The app registry will not be ready at this point, so we cannot
            # use get_field().
            query = self.order_with_respect_to
            try:
                self.order_with_respect_to = next(
                    f for f in self._get_fields(reverse=False)
                    if f.name == query or f.attname == query
                )
            except StopIteration:
                raise FieldDoesNotExist('%s has no field named %r' % (self.object_name, query))

            self.ordering = ('_order',)
            if not any(isinstance(field, OrderWrt) for field in model._meta.local_fields):
                model.add_to_class('_order', OrderWrt())
        else:
            self.order_with_respect_to = None

        if self.pk is None:
            if self.parents:
                # Promote the first parent link in lieu of adding yet another
                # field.
                field = next(six.itervalues(self.parents))
                # Look for a local field with the same name as the
                # first parent link. If a local field has already been
                # created, use it instead of promoting the parent
                already_created = [fld for fld in self.local_fields if fld.name == field.name]
                if already_created:
                    field = already_created[0]
                field.primary_key = True
                self.setup_pk(field)
            else:
                auto = AutoField(verbose_name='ID', primary_key=True,
                        auto_created=True)
                model.add_to_class('id', auto) 

def test_itervalues(self):
        self.context['x'] = 1
        self.context.modified = False
        self.context.accessed = False
        i = six.itervalues(self.context)
        self.assertTrue(hasattr(i, '__iter__'))
        self.assertTrue(self.context.accessed)
        self.assertFalse(self.context.modified)
        self.assertEqual(list(i), [1]) 

def get_action_choices(self, request, default_choices=BLANK_CHOICE_DASH):
        """
        Return a list of choices for use in a form object.  Each choice is a
        tuple (name, description).
        """
        choices = [] + default_choices
        for func, name, description in six.itervalues(self.get_actions(request)):
            choice = (name, description % model_format_dict(self.opts))
            choices.append(choice)
        return choices 

def sitemap(request, sitemaps, section=None,
            template_name='sitemap.xml', content_type='application/xml'):

    req_protocol = request.scheme
    req_site = get_current_site(request)

    if section is not None:
        if section not in sitemaps:
            raise Http404("No sitemap available for section: %r" % section)
        maps = [sitemaps[section]]
    else:
        maps = list(six.itervalues(sitemaps))
    page = request.GET.get("p", 1)

    urls = []
    for site in maps:
        try:
            if callable(site):
                site = site()
            urls.extend(site.get_urls(page=page, site=req_site,
                                      protocol=req_protocol))
        except EmptyPage:
            raise Http404("Page %s empty" % page)
        except PageNotAnInteger:
            raise Http404("No page '%s'" % page)
    response = TemplateResponse(request, template_name, {'urlset': urls},
                                content_type=content_type)
    if hasattr(site, 'latest_lastmod'):
        # if latest_lastmod is defined for site, set header so as
        # ConditionalGetMiddleware is able to send 304 NOT MODIFIED
        lastmod = site.latest_lastmod
        response['Last-Modified'] = http_date(
            timegm(
                lastmod.utctimetuple() if isinstance(lastmod, datetime.datetime)
                else lastmod.timetuple()
            )
        )
    return response 

def __init__(self, form, inline_formsets):
        super(AdminErrorList, self).__init__()

        if form.is_bound:
            self.extend(list(six.itervalues(form.errors)))
            for inline_formset in inline_formsets:
                self.extend(inline_formset.non_form_errors())
                for errors_in_inline_form in inline_formset.errors:
                    self.extend(list(six.itervalues(errors_in_inline_form))) 

def _prepare(self, model):
        if self.order_with_respect_to:
            # The app registry will not be ready at this point, so we cannot
            # use get_field().
            query = self.order_with_respect_to
            try:
                self.order_with_respect_to = next(
                    f for f in self._get_fields(reverse=False)
                    if f.name == query or f.attname == query
                )
            except StopIteration:
                raise FieldDoesNotExist("%s has no field named '%s'" % (self.object_name, query))

            self.ordering = ('_order',)
            if not any(isinstance(field, OrderWrt) for field in model._meta.local_fields):
                model.add_to_class('_order', OrderWrt())
        else:
            self.order_with_respect_to = None

        if self.pk is None:
            if self.parents:
                # Promote the first parent link in lieu of adding yet another
                # field.
                field = next(six.itervalues(self.parents))
                # Look for a local field with the same name as the
                # first parent link. If a local field has already been
                # created, use it instead of promoting the parent
                already_created = [fld for fld in self.local_fields if fld.name == field.name]
                if already_created:
                    field = already_created[0]
                field.primary_key = True
                self.setup_pk(field)
                if not field.remote_field.parent_link:
                    warnings.warn(
                        'Add parent_link=True to %s as an implicit link is '
                        'deprecated.' % field, RemovedInDjango20Warning
                    )
            else:
                auto = AutoField(verbose_name='ID', primary_key=True, auto_created=True)
                model.add_to_class('id', auto) 

def list(self, ignore_patterns):
        """
        List all files in all app storages.
        """
        for storage in six.itervalues(self.storages):
            if storage.exists(''):  # check if storage location exists
                for path in utils.get_files(storage, ignore_patterns):
                    yield path, storage 

def check_generic_foreign_keys(**kwargs):
    from .fields import GenericForeignKey

    errors = []
    fields = (obj
        for cls in apps.get_models()
        for obj in six.itervalues(vars(cls))
        if isinstance(obj, GenericForeignKey))
    for field in fields:
        errors.extend(field.check())
    return errors 

def has_joins(queryset):
    """Return True iff. a queryset includes joins.

    If this is the case, it is possible for the queryset
    to return duplicate results.
    """
    for join in six.itervalues(queryset.query.alias_map):
        if join.join_type:
            return True
    return False 

def as_sql(self):
        """ Generate SQL queries that perform related deletion """
        # List of (sql, params) tuples to perform deletion
        query_list = []

        for model, instances in self.data.items():
            self.data[model] = sorted(instances, key=attrgetter("pk"))
        self.sort()
        # Do not send pre_delete signals as in .delete()

        # Fast deletes
        for qs in self.fast_deletes:
            # TODO Check for any potential caveats from complex queries - assume none are generated by Collector

            # Clone queryset into DeleteQuery to use .as_sql()
            query_list.append(qs.query.clone(klass=sql.DeleteQuery).get_compiler(self.using).as_sql())

        # update fields
        for model, instances_for_fieldvalues in six.iteritems(self.field_updates):
            query = sql.UpdateQuery(model)
            for (field, value), instances in six.iteritems(instances_for_fieldvalues):
                query.add_update_values({field.name: value})
                query.add_q(models.Q(pk__in=[obj.pk for obj in instances]))
                query_list.append(query.get_compiler(using=self.using).as_sql())

        # reverse instance collections
        for instances in six.itervalues(self.data):
            instances.reverse()

        # delete instances
        for model, instances in six.iteritems(self.data):
            query = sql.DeleteQuery(model)
            pk_list = [obj.pk for obj in instances]
            query.where = query.where_class()
            query.add_q(models.Q(pk__in=pk_list))
            query_list.append(query.get_compiler(using=self.using).as_sql())

        # Do not update instances as in .delete()
        return query_list 

def delete(self):
        # sort instance collections
        for model, instances in self.data.items():
            self.data[model] = sorted(instances, key=attrgetter("pk"))

        # if possible, bring the models in an order suitable for databases that
        # don't support transactions or cannot defer constraint checks until the
        # end of a transaction.
        self.sort()

        with transaction.atomic(using=self.using, savepoint=False):
            # send pre_delete signals
            for model, obj in self.instances_with_model():
                if not model._meta.auto_created:
                    signals.pre_delete.send(
                        sender=model, instance=obj, using=self.using
                    )

            # fast deletes
            for qs in self.fast_deletes:
                qs._raw_delete(using=self.using)

            # update fields
            for model, instances_for_fieldvalues in six.iteritems(self.field_updates):
                query = sql.UpdateQuery(model)
                for (field, value), instances in six.iteritems(instances_for_fieldvalues):
                    query.update_batch([obj.pk for obj in instances],
                                       {field.name: value}, self.using)

            # reverse instance collections
            for instances in six.itervalues(self.data):
                instances.reverse()

            # delete instances
            for model, instances in six.iteritems(self.data):
                query = sql.DeleteQuery(model)
                pk_list = [obj.pk for obj in instances]
                query.delete_batch(pk_list, self.using)

                if not model._meta.auto_created:
                    for obj in instances:
                        signals.post_delete.send(
                            sender=model, instance=obj, using=self.using
                        )

        # update collected instances
        for model, instances_for_fieldvalues in six.iteritems(self.field_updates):
            for (field, value), instances in six.iteritems(instances_for_fieldvalues):
                for obj in instances:
                    setattr(obj, field.attname, value)
        for model, instances in six.iteritems(self.data):
            for instance in instances:
                setattr(instance, model._meta.pk.attname, None) 

def delete(self):
        # sort instance collections
        for model, instances in self.data.items():
            self.data[model] = sorted(instances, key=attrgetter("pk"))

        # if possible, bring the models in an order suitable for databases that
        # don't support transactions or cannot defer constraint checks until the
        # end of a transaction.
        self.sort()
        # number of objects deleted for each model label
        deleted_counter = Counter()

        with transaction.atomic(using=self.using, savepoint=False):
            # send pre_delete signals
            for model, obj in self.instances_with_model():
                if not model._meta.auto_created:
                    signals.pre_delete.send(
                        sender=model, instance=obj, using=self.using
                    )

            # fast deletes
            for qs in self.fast_deletes:
                count = qs._raw_delete(using=self.using)
                deleted_counter[qs.model._meta.label] += count

            # update fields
            for model, instances_for_fieldvalues in six.iteritems(self.field_updates):
                query = sql.UpdateQuery(model)
                for (field, value), instances in six.iteritems(instances_for_fieldvalues):
                    query.update_batch([obj.pk for obj in instances],
                                       {field.name: value}, self.using)

            # reverse instance collections
            for instances in six.itervalues(self.data):
                instances.reverse()

            # delete instances
            for model, instances in six.iteritems(self.data):
                query = sql.DeleteQuery(model)
                pk_list = [obj.pk for obj in instances]
                count = query.delete_batch(pk_list, self.using)
                deleted_counter[model._meta.label] += count

                if not model._meta.auto_created:
                    for obj in instances:
                        signals.post_delete.send(
                            sender=model, instance=obj, using=self.using
                        )

        # update collected instances
        for model, instances_for_fieldvalues in six.iteritems(self.field_updates):
            for (field, value), instances in six.iteritems(instances_for_fieldvalues):
                for obj in instances:
                    setattr(obj, field.attname, value)
        for model, instances in six.iteritems(self.data):
            for instance in instances:
                setattr(instance, model._meta.pk.attname, None)
        return sum(deleted_counter.values()), dict(deleted_counter) 

def delete(self):
        # sort instance collections
        for model, instances in self.data.items():
            self.data[model] = sorted(instances, key=attrgetter("pk"))

        # if possible, bring the models in an order suitable for databases that
        # don't support transactions or cannot defer constraint checks until the
        # end of a transaction.
        self.sort()
        # number of objects deleted for each model label
        deleted_counter = Counter()

        with transaction.atomic(using=self.using, savepoint=False):
            # send pre_delete signals
            for model, obj in self.instances_with_model():
                if not model._meta.auto_created:
                    signals.pre_delete.send(
                        sender=model, instance=obj, using=self.using
                    )

            # fast deletes
            for qs in self.fast_deletes:
                count = qs._raw_delete(using=self.using)
                deleted_counter[qs.model._meta.label] += count

            # update fields
            for model, instances_for_fieldvalues in six.iteritems(self.field_updates):
                query = sql.UpdateQuery(model)
                for (field, value), instances in six.iteritems(instances_for_fieldvalues):
                    query.update_batch([obj.pk for obj in instances],
                                       {field.name: value}, self.using)

            # reverse instance collections
            for instances in six.itervalues(self.data):
                instances.reverse()

            # delete instances
            for model, instances in six.iteritems(self.data):
                query = sql.DeleteQuery(model)
                pk_list = [obj.pk for obj in instances]
                count = query.delete_batch(pk_list, self.using)
                deleted_counter[model._meta.label] += count

                if not model._meta.auto_created:
                    for obj in instances:
                        signals.post_delete.send(
                            sender=model, instance=obj, using=self.using
                        )

        # update collected instances
        for model, instances_for_fieldvalues in six.iteritems(self.field_updates):
            for (field, value), instances in six.iteritems(instances_for_fieldvalues):
                for obj in instances:
                    setattr(obj, field.attname, value)
        for model, instances in six.iteritems(self.data):
            for instance in instances:
                setattr(instance, model._meta.pk.attname, None)
        return sum(deleted_counter.values()), dict(deleted_counter) 

def collect(self, objs, source=None, nullable=False, collect_related=True,
                source_attr=None, reverse_dependency=False, keep_parents=False):
        """
        Adds 'objs' to the collection of objects to be deleted as well as all
        parent instances.  'objs' must be a homogeneous iterable collection of
        model instances (e.g. a QuerySet).  If 'collect_related' is True,
        related objects will be handled by their respective on_delete handler.

        If the call is the result of a cascade, 'source' should be the model
        that caused it and 'nullable' should be set to True, if the relation
        can be null.

        If 'reverse_dependency' is True, 'source' will be deleted before the
        current model, rather than after. (Needed for cascading to parent
        models, the one case in which the cascade follows the forwards
        direction of an FK rather than the reverse direction.)

        If 'keep_parents' is True, data of parent model's will be not deleted.
        """
        if self.can_fast_delete(objs):
            self.fast_deletes.append(objs)
            return
        new_objs = self.add(objs, source, nullable,
                            reverse_dependency=reverse_dependency)
        if not new_objs:
            return

        model = new_objs[0].__class__

        if not keep_parents:
            # Recursively collect concrete model's parent models, but not their
            # related objects. These will be found by meta.get_fields()
            concrete_model = model._meta.concrete_model
            for ptr in six.itervalues(concrete_model._meta.parents):
                if ptr:
                    parent_objs = [getattr(obj, ptr.name) for obj in new_objs]
                    self.collect(parent_objs, source=model,
                                 source_attr=ptr.remote_field.related_name,
                                 collect_related=False,
                                 reverse_dependency=True)
        if collect_related:
            parents = model._meta.parents
            for related in get_candidate_relations_to_delete(model._meta):
                # Preserve parent reverse relationships if keep_parents=True.
                if keep_parents and related.model in parents:
                    continue
                field = related.field
                if field.remote_field.on_delete == DO_NOTHING:
                    continue
                batches = self.get_del_batches(new_objs, field)
                for batch in batches:
                    sub_objs = self.related_objects(related, batch)
                    if self.can_fast_delete(sub_objs, from_field=field):
                        self.fast_deletes.append(sub_objs)
                    elif sub_objs:
                        field.remote_field.on_delete(self, field, sub_objs, self.using)
            for field in model._meta.private_fields:
                if hasattr(field, 'bulk_related_objects'):
                    # It's something like generic foreign key.
                    sub_objs = field.bulk_related_objects(new_objs, self.using)
                    self.collect(sub_objs, source=model, nullable=True) 

def delete(self):
        # sort instance collections
        for model, instances in self.data.items():
            self.data[model] = sorted(instances, key=attrgetter("pk"))

        # if possible, bring the models in an order suitable for databases that
        # don't support transactions or cannot defer constraint checks until the
        # end of a transaction.
        self.sort()
        # number of objects deleted for each model label
        deleted_counter = Counter()

        with transaction.atomic(using=self.using, savepoint=False):
            # send pre_delete signals
            for model, obj in self.instances_with_model():
                if not model._meta.auto_created:
                    signals.pre_delete.send(
                        sender=model, instance=obj, using=self.using
                    )

            # fast deletes
            for qs in self.fast_deletes:
                count = qs._raw_delete(using=self.using)
                deleted_counter[qs.model._meta.label] += count

            # update fields
            for model, instances_for_fieldvalues in six.iteritems(self.field_updates):
                query = sql.UpdateQuery(model)
                for (field, value), instances in six.iteritems(instances_for_fieldvalues):
                    query.update_batch([obj.pk for obj in instances],
                                       {field.name: value}, self.using)

            # reverse instance collections
            for instances in six.itervalues(self.data):
                instances.reverse()

            # delete instances
            for model, instances in six.iteritems(self.data):
                query = sql.DeleteQuery(model)
                pk_list = [obj.pk for obj in instances]
                count = query.delete_batch(pk_list, self.using)
                deleted_counter[model._meta.label] += count

                if not model._meta.auto_created:
                    for obj in instances:
                        signals.post_delete.send(
                            sender=model, instance=obj, using=self.using
                        )

        # update collected instances
        for model, instances_for_fieldvalues in six.iteritems(self.field_updates):
            for (field, value), instances in six.iteritems(instances_for_fieldvalues):
                for obj in instances:
                    setattr(obj, field.attname, value)
        for model, instances in six.iteritems(self.data):
            for instance in instances:
                setattr(instance, model._meta.pk.attname, None)
        return sum(deleted_counter.values()), dict(deleted_counter) 

def collect(self, objs, source=None, nullable=False, collect_related=True,
            source_attr=None, reverse_dependency=False, keep_parents=False):
        """
        Adds 'objs' to the collection of objects to be deleted as well as all
        parent instances.  'objs' must be a homogeneous iterable collection of
        model instances (e.g. a QuerySet).  If 'collect_related' is True,
        related objects will be handled by their respective on_delete handler.

        If the call is the result of a cascade, 'source' should be the model
        that caused it and 'nullable' should be set to True, if the relation
        can be null.

        If 'reverse_dependency' is True, 'source' will be deleted before the
        current model, rather than after. (Needed for cascading to parent
        models, the one case in which the cascade follows the forwards
        direction of an FK rather than the reverse direction.)

        If 'keep_parents' is True, data of parent model's will be not deleted.
        """
        if self.can_fast_delete(objs):
            self.fast_deletes.append(objs)
            return
        new_objs = self.add(objs, source, nullable,
                            reverse_dependency=reverse_dependency)
        if not new_objs:
            return

        model = new_objs[0].__class__

        if not keep_parents:
            # Recursively collect concrete model's parent models, but not their
            # related objects. These will be found by meta.get_fields()
            concrete_model = model._meta.concrete_model
            for ptr in six.itervalues(concrete_model._meta.parents):
                if ptr:
                    # FIXME: This seems to be buggy and execute a query for each
                    # parent object fetch. We have the parent data in the obj,
                    # but we don't have a nice way to turn that data into parent
                    # object instance.
                    parent_objs = [getattr(obj, ptr.name) for obj in new_objs]
                    self.collect(parent_objs, source=model,
                                 source_attr=ptr.remote_field.related_name,
                                 collect_related=False,
                                 reverse_dependency=True)
        if collect_related:
            for related in get_candidate_relations_to_delete(model._meta):
                field = related.field
                if field.remote_field.on_delete == DO_NOTHING:
                    continue
                batches = self.get_del_batches(new_objs, field)
                for batch in batches:
                    sub_objs = self.related_objects(related, batch)
                    if self.can_fast_delete(sub_objs, from_field=field):
                        self.fast_deletes.append(sub_objs)
                    elif sub_objs:
                        field.remote_field.on_delete(self, field, sub_objs, self.using)
            for field in model._meta.virtual_fields:
                if hasattr(field, 'bulk_related_objects'):
                    # It's something like generic foreign key.
                    sub_objs = field.bulk_related_objects(new_objs, self.using)
                    self.collect(sub_objs, source=model, nullable=True) 

def version_matrix(request):
    matrix = defaultdict(partial(defaultdict, LatestList))
    latest = defaultdict(list)
    groups = defaultdict(list)

    judges = {judge.id: judge.name for judge in Judge.objects.filter(online=True)}
    languages = Language.objects.filter(judges__online=True).distinct()

    for runtime in RuntimeVersion.objects.filter(judge__online=True).order_by('priority'):
        matrix[runtime.judge_id][runtime.language_id].append(runtime)

    for judge, data in six.iteritems(matrix):
        name_tuple = judges[judge].rpartition('.')
        groups[name_tuple[0] or name_tuple[-1]].append((judges[judge], data))

    matrix = {}
    for group, data in six.iteritems(groups):
        if len(data) == 1:
            judge, data = data[0]
            matrix[judge] = data
            continue

        ds = list(range(len(data)))
        size = [1] * len(data)
        for i, (p, x) in enumerate(data):
            if ds[i] != i:
                continue
            for j, (q, y) in enumerate(data):
                if i != j and compare_version_list(x, y):
                    ds[j] = i
                    size[i] += 1
                    size[j] = 0

        rep = max(range(len(data)), key=size.__getitem__)
        matrix[group] = data[rep][1]
        for i, (j, x) in enumerate(data):
            if ds[i] != rep:
                matrix[j] = x

    for data in six.itervalues(matrix):
        for language, versions in six.iteritems(data):
            versions.versions = [version.parse(runtime.version) for runtime in versions]
            if versions.versions > latest[language]:
                latest[language] = versions.versions

    for data in six.itervalues(matrix):
        for language, versions in six.iteritems(data):
            versions.is_latest = versions.versions == latest[language]

    languages = sorted(languages, key=lambda lang: version.parse(lang.name))
    return render(request, 'status/versions.html', {
        'title': _('Version matrix'),
        'judges': sorted(matrix.keys()),
        'languages': languages,
        'matrix': matrix,
    }) 

def delete(self):
        # sort instance collections
        for model, instances in self.data.items():
            self.data[model] = sorted(instances, key=attrgetter("pk"))

        # if possible, bring the models in an order suitable for databases that
        # don't support transactions or cannot defer constraint checks until the
        # end of a transaction.
        self.sort()

        # send pre_delete signals
        for model, obj in self.instances_with_model():
            if not model._meta.auto_created:
                signals.pre_delete.send(
                    sender=model, instance=obj, using=self.using
                )

        # fast deletes
        for qs in self.fast_deletes:
            qs._raw_delete(using=self.using)

        # update fields
        for model, instances_for_fieldvalues in six.iteritems(self.field_updates):
            query = sql.UpdateQuery(model)
            for (field, value), instances in six.iteritems(instances_for_fieldvalues):
                query.update_batch([obj.pk for obj in instances],
                                   {field.name: value}, self.using)

        # reverse instance collections
        for instances in six.itervalues(self.data):
            instances.reverse()

        # delete batches
        for model, batches in six.iteritems(self.batches):
            query = sql.DeleteQuery(model)
            for field, instances in six.iteritems(batches):
                query.delete_batch([obj.pk for obj in instances], self.using, field)

        # delete instances
        for model, instances in six.iteritems(self.data):
            query = sql.DeleteQuery(model)
            pk_list = [obj.pk for obj in instances]
            query.delete_batch(pk_list, self.using)

        # send post_delete signals
        for model, obj in self.instances_with_model():
            if not model._meta.auto_created:
                signals.post_delete.send(
                    sender=model, instance=obj, using=self.using
                )

        # update collected instances
        for model, instances_for_fieldvalues in six.iteritems(self.field_updates):
            for (field, value), instances in six.iteritems(instances_for_fieldvalues):
                for obj in instances:
                    setattr(obj, field.attname, value)
        for model, instances in six.iteritems(self.data):
            for instance in instances:
                setattr(instance, model._meta.pk.attname, None) 

def get_models(self, app_mod=None,
                   include_auto_created=False, include_deferred=False,
                   only_installed=True, include_swapped=False):
        """
        Given a module containing models, returns a list of the models.
        Otherwise returns a list of all installed models.

        By default, auto-created models (i.e., m2m models without an
        explicit intermediate table) are not included. However, if you
        specify include_auto_created=True, they will be.

        By default, models created to satisfy deferred attribute
        queries are *not* included in the list of models. However, if
        you specify include_deferred, they will be.

        By default, models that aren't part of installed apps will *not*
        be included in the list of models. However, if you specify
        only_installed=False, they will be.

        By default, models that have been swapped out will *not* be
        included in the list of models. However, if you specify
        include_swapped, they will be.
        """
        cache_key = (app_mod, include_auto_created, include_deferred, only_installed, include_swapped)
        try:
            return self._get_models_cache[cache_key]
        except KeyError:
            pass
        self._populate()
        if app_mod:
            if app_mod in self.app_store:
                app_list = [self.app_models.get(self._label_for(app_mod),
                                                SortedDict())]
            else:
                app_list = []
        else:
            if only_installed:
                app_list = [self.app_models.get(app_label, SortedDict())
                            for app_label in six.iterkeys(self.app_labels)]
            else:
                app_list = six.itervalues(self.app_models)
        model_list = []
        for app in app_list:
            model_list.extend(
                model for model in app.values()
                if ((not model._deferred or include_deferred) and
                    (not model._meta.auto_created or include_auto_created) and
                    (not model._meta.swapped or include_swapped))
            )
        self._get_models_cache[cache_key] = model_list
        return model_list