Python codecs.BOM_UTF8 Examples

def _detect_encoding(self, fileid):
        if isinstance(fileid, PathPointer):
            s = fileid.open().readline()
        else:
            with open(fileid, 'rb') as infile:
                s = infile.readline()
        if s.startswith(codecs.BOM_UTF16_BE):
            return 'utf-16-be'
        if s.startswith(codecs.BOM_UTF16_LE):
            return 'utf-16-le'
        if s.startswith(codecs.BOM_UTF32_BE):
            return 'utf-32-be'
        if s.startswith(codecs.BOM_UTF32_LE):
            return 'utf-32-le'
        if s.startswith(codecs.BOM_UTF8):
            return 'utf-8'
        m = re.match(br'\s*<\?xml\b.*\bencoding="([^"]+)"', s)
        if m:
            return m.group(1).decode()
        m = re.match(br"\s*<\?xml\b.*\bencoding='([^']+)'", s)
        if m:
            return m.group(1).decode()
        # No encoding found -- what should the default be?
        return 'utf-8' 

def _load_gitignore_file(source_location):
    # reference: https://git-scm.com/docs/gitignore
    git_ignore_file = os.path.join(source_location, ".gitignore")
    if not os.path.exists(git_ignore_file):
        return None, 0

    encoding = "utf-8"
    header = open(git_ignore_file, "rb").read(len(codecs.BOM_UTF8))
    if header.startswith(codecs.BOM_UTF8):
        encoding = "utf-8-sig"

    ignore_list = []

    for line in open(git_ignore_file, 'r', encoding=encoding).readlines():
        rule = line.rstrip()

        # skip empty line and comment
        if not rule or rule.startswith('#'):
            continue

        # the ignore rule at the end has higher priority
        ignore_list = [IgnoreRule(rule)] + ignore_list

    return ignore_list, len(ignore_list) 

def _buffer_decode(self, input, errors, final):
        if self.first:
            if len(input) < 3:
                if codecs.BOM_UTF8.startswith(input):
                    # not enough data to decide if this really is a BOM
                    # => try again on the next call
                    return ("", 0)
                else:
                    self.first = 0
            else:
                self.first = 0
                if input[:3] == codecs.BOM_UTF8:
                    (output, consumed) = \
                       codecs.utf_8_decode(input[3:], errors, final)
                    return (output, consumed+3)
        return codecs.utf_8_decode(input, errors, final) 

def load_file(self):
        with open(self.__wallet_path, 'rb') as f:
            content = f.read()
            if content.startswith(codecs.BOM_UTF8):
                content = content[len(codecs.BOM_UTF8):]
            content = content.decode('utf-8')
            wallet_dict = json.loads(content)
            create_time = wallet_dict.get('createTime', '')
            default_id = wallet_dict.get('defaultOntid', '')
            default_address = wallet_dict.get('defaultAccountAddress', '')
            identities = wallet_dict.get('identities', list())
            try:
                scrypt_dict = wallet_dict['scrypt']
                scrypt_obj = Scrypt(scrypt_dict.get('n', 16384), scrypt_dict.get('r', 8), scrypt_dict.get('p', 8),
                                    scrypt_dict.get('dk_len', 64))
                wallet = WalletData(wallet_dict['name'], wallet_dict['version'], create_time, default_id,
                                    default_address, scrypt_obj, identities, wallet_dict['accounts'])
            except KeyError as e:
                raise SDKException(ErrorCode.param_err(f'wallet file format error: {e}.'))
        return wallet 

def test_all(self):
        api = (
            "encode", "decode",
            "register", "CodecInfo", "Codec", "IncrementalEncoder",
            "IncrementalDecoder", "StreamReader", "StreamWriter", "lookup",
            "getencoder", "getdecoder", "getincrementalencoder",
            "getincrementaldecoder", "getreader", "getwriter",
            "register_error", "lookup_error",
            "strict_errors", "replace_errors", "ignore_errors",
            "xmlcharrefreplace_errors", "backslashreplace_errors",
            "open", "EncodedFile",
            "iterencode", "iterdecode",
            "BOM", "BOM_BE", "BOM_LE",
            "BOM_UTF8", "BOM_UTF16", "BOM_UTF16_BE", "BOM_UTF16_LE",
            "BOM_UTF32", "BOM_UTF32_BE", "BOM_UTF32_LE",
            "BOM32_BE", "BOM32_LE", "BOM64_BE", "BOM64_LE",  # Undocumented
            "StreamReaderWriter", "StreamRecoder",
        )
        self.assertEqual(sorted(api), sorted(codecs.__all__))
        for api in codecs.__all__:
            getattr(codecs, api) 

def test_stream_bom(self):
        unistring = u"ABC\u00A1\u2200XYZ"
        bytestring = codecs.BOM_UTF8 + "ABC\xC2\xA1\xE2\x88\x80XYZ"

        reader = codecs.getreader("utf-8-sig")
        for sizehint in [None] + range(1, 11) + \
                        [64, 128, 256, 512, 1024]:
            istream = reader(StringIO.StringIO(bytestring))
            ostream = StringIO.StringIO()
            while 1:
                if sizehint is not None:
                    data = istream.read(sizehint)
                else:
                    data = istream.read()

                if not data:
                    break
                ostream.write(data)

            got = ostream.getvalue()
            self.assertEqual(got, unistring) 

def decode(input, errors='strict'):
    prefix = 0
    if input[:3] == codecs.BOM_UTF8:
        input = input[3:]
        prefix = 3
    (output, consumed) = codecs.utf_8_decode(input, errors, True)
    return (output, consumed+prefix) 

def guess_json_utf(data):
    # JSON always starts with two ASCII characters, so detection is as
    # easy as counting the nulls and from their location and count
    # determine the encoding. Also detect a BOM, if present.
    sample = data[:4]
    if sample in (codecs.BOM_UTF32_LE, codecs.BOM32_BE):
        return 'utf-32'     # BOM included
    if sample[:3] == codecs.BOM_UTF8:
        return 'utf-8-sig'  # BOM included, MS style (discouraged)
    if sample[:2] in (codecs.BOM_UTF16_LE, codecs.BOM_UTF16_BE):
        return 'utf-16'     # BOM included
    nullcount = sample.count(_null)
    if nullcount == 0:
        return 'utf-8'
    if nullcount == 2:
        if sample[::2] == _null2:   # 1st and 3rd are null
            return 'utf-16-be'
        if sample[1::2] == _null2:  # 2nd and 4th are null
            return 'utf-16-le'
        # Did not detect 2 valid UTF-16 ascii-range characters
    if nullcount == 3:
        if sample[:3] == _null3:
            return 'utf-32-be'
        if sample[1:] == _null3:
            return 'utf-32-le'
        # Did not detect a valid UTF-32 ascii-range character
    return None 

def encode(self, input, final=False):
        if self.first:
            self.first = 0
            return codecs.BOM_UTF8 + \
                   codecs.utf_8_encode(input, self.errors)[0]
        else:
            return codecs.utf_8_encode(input, self.errors)[0] 

def guess_json_utf(data):
    """
    :rtype: str
    """
    # JSON always starts with two ASCII characters, so detection is as
    # easy as counting the nulls and from their location and count
    # determine the encoding. Also detect a BOM, if present.
    sample = data[:4]
    if sample in (codecs.BOM_UTF32_LE, codecs.BOM_UTF32_BE):
        return 'utf-32'     # BOM included
    if sample[:3] == codecs.BOM_UTF8:
        return 'utf-8-sig'  # BOM included, MS style (discouraged)
    if sample[:2] in (codecs.BOM_UTF16_LE, codecs.BOM_UTF16_BE):
        return 'utf-16'     # BOM included
    nullcount = sample.count(_null)
    if nullcount == 0:
        return 'utf-8'
    if nullcount == 2:
        if sample[::2] == _null2:   # 1st and 3rd are null
            return 'utf-16-be'
        if sample[1::2] == _null2:  # 2nd and 4th are null
            return 'utf-16-le'
        # Did not detect 2 valid UTF-16 ascii-range characters
    if nullcount == 3:
        if sample[:3] == _null3:
            return 'utf-32-be'
        if sample[1:] == _null3:
            return 'utf-32-le'
        # Did not detect a valid UTF-32 ascii-range character
    return None 

def guess_json_utf(data):
    # JSON always starts with two ASCII characters, so detection is as
    # easy as counting the nulls and from their location and count
    # determine the encoding. Also detect a BOM, if present.
    sample = data[:4]
    if sample in (codecs.BOM_UTF32_LE, codecs.BOM32_BE):
        return 'utf-32'     # BOM included
    if sample[:3] == codecs.BOM_UTF8:
        return 'utf-8-sig'  # BOM included, MS style (discouraged)
    if sample[:2] in (codecs.BOM_UTF16_LE, codecs.BOM_UTF16_BE):
        return 'utf-16'     # BOM included
    nullcount = sample.count(_null)
    if nullcount == 0:
        return 'utf-8'
    if nullcount == 2:
        if sample[::2] == _null2:   # 1st and 3rd are null
            return 'utf-16-be'
        if sample[1::2] == _null2:  # 2nd and 4th are null
            return 'utf-16-le'
        # Did not detect 2 valid UTF-16 ascii-range characters
    if nullcount == 3:
        if sample[:3] == _null3:
            return 'utf-32-be'
        if sample[1:] == _null3:
            return 'utf-32-le'
        # Did not detect a valid UTF-32 ascii-range character
    return None 

def guess_json_utf(data):
    # JSON always starts with two ASCII characters, so detection is as
    # easy as counting the nulls and from their location and count
    # determine the encoding. Also detect a BOM, if present.
    sample = data[:4]
    if sample in (codecs.BOM_UTF32_LE, codecs.BOM32_BE):
        return 'utf-32'     # BOM included
    if sample[:3] == codecs.BOM_UTF8:
        return 'utf-8-sig'  # BOM included, MS style (discouraged)
    if sample[:2] in (codecs.BOM_UTF16_LE, codecs.BOM_UTF16_BE):
        return 'utf-16'     # BOM included
    nullcount = sample.count(_null)
    if nullcount == 0:
        return 'utf-8'
    if nullcount == 2:
        if sample[::2] == _null2:   # 1st and 3rd are null
            return 'utf-16-be'
        if sample[1::2] == _null2:  # 2nd and 4th are null
            return 'utf-16-le'
        # Did not detect 2 valid UTF-16 ascii-range characters
    if nullcount == 3:
        if sample[:3] == _null3:
            return 'utf-32-be'
        if sample[1:] == _null3:
            return 'utf-32-le'
        # Did not detect a valid UTF-32 ascii-range character
    return None 

def detectBOM(self):
        """Attempts to detect at BOM at the start of the stream. If
        an encoding can be determined from the BOM return the name of the
        encoding otherwise return None"""
        bomDict = {
            codecs.BOM_UTF8: 'utf-8',
            codecs.BOM_UTF16_LE: 'utf-16le', codecs.BOM_UTF16_BE: 'utf-16be',
            codecs.BOM_UTF32_LE: 'utf-32le', codecs.BOM_UTF32_BE: 'utf-32be'
        }

        # Go to beginning of file and read in 4 bytes
        string = self.rawStream.read(4)
        assert isinstance(string, bytes)

        # Try detecting the BOM using bytes from the string
        encoding = bomDict.get(string[:3])         # UTF-8
        seek = 3
        if not encoding:
            # Need to detect UTF-32 before UTF-16
            encoding = bomDict.get(string)         # UTF-32
            seek = 4
            if not encoding:
                encoding = bomDict.get(string[:2])  # UTF-16
                seek = 2

        # Set the read position past the BOM if one was found, otherwise
        # set it to the start of the stream
        if encoding:
            self.rawStream.seek(seek)
            return lookupEncoding(encoding)
        else:
            self.rawStream.seek(0)
            return None 

def guess_json_utf(data):
    """
    :rtype: str
    """
    # JSON always starts with two ASCII characters, so detection is as
    # easy as counting the nulls and from their location and count
    # determine the encoding. Also detect a BOM, if present.
    sample = data[:4]
    if sample in (codecs.BOM_UTF32_LE, codecs.BOM32_BE):
        return 'utf-32'     # BOM included
    if sample[:3] == codecs.BOM_UTF8:
        return 'utf-8-sig'  # BOM included, MS style (discouraged)
    if sample[:2] in (codecs.BOM_UTF16_LE, codecs.BOM_UTF16_BE):
        return 'utf-16'     # BOM included
    nullcount = sample.count(_null)
    if nullcount == 0:
        return 'utf-8'
    if nullcount == 2:
        if sample[::2] == _null2:   # 1st and 3rd are null
            return 'utf-16-be'
        if sample[1::2] == _null2:  # 2nd and 4th are null
            return 'utf-16-le'
        # Did not detect 2 valid UTF-16 ascii-range characters
    if nullcount == 3:
        if sample[:3] == _null3:
            return 'utf-32-be'
        if sample[1:] == _null3:
            return 'utf-32-le'
        # Did not detect a valid UTF-32 ascii-range character
    return None 

def guess_json_utf(data):
    # JSON always starts with two ASCII characters, so detection is as
    # easy as counting the nulls and from their location and count
    # determine the encoding. Also detect a BOM, if present.
    sample = data[:4]
    if sample in (codecs.BOM_UTF32_LE, codecs.BOM32_BE):
        return 'utf-32'     # BOM included
    if sample[:3] == codecs.BOM_UTF8:
        return 'utf-8-sig'  # BOM included, MS style (discouraged)
    if sample[:2] in (codecs.BOM_UTF16_LE, codecs.BOM_UTF16_BE):
        return 'utf-16'     # BOM included
    nullcount = sample.count(_null)
    if nullcount == 0:
        return 'utf-8'
    if nullcount == 2:
        if sample[::2] == _null2:   # 1st and 3rd are null
            return 'utf-16-be'
        if sample[1::2] == _null2:  # 2nd and 4th are null
            return 'utf-16-le'
        # Did not detect 2 valid UTF-16 ascii-range characters
    if nullcount == 3:
        if sample[:3] == _null3:
            return 'utf-32-be'
        if sample[1:] == _null3:
            return 'utf-32-le'
        # Did not detect a valid UTF-32 ascii-range character
    return None 

def guess_json_utf(data):
    # JSON always starts with two ASCII characters, so detection is as
    # easy as counting the nulls and from their location and count
    # determine the encoding. Also detect a BOM, if present.
    sample = data[:4]
    if sample in (codecs.BOM_UTF32_LE, codecs.BOM32_BE):
        return 'utf-32'     # BOM included
    if sample[:3] == codecs.BOM_UTF8:
        return 'utf-8-sig'  # BOM included, MS style (discouraged)
    if sample[:2] in (codecs.BOM_UTF16_LE, codecs.BOM_UTF16_BE):
        return 'utf-16'     # BOM included
    nullcount = sample.count(_null)
    if nullcount == 0:
        return 'utf-8'
    if nullcount == 2:
        if sample[::2] == _null2:   # 1st and 3rd are null
            return 'utf-16-be'
        if sample[1::2] == _null2:  # 2nd and 4th are null
            return 'utf-16-le'
        # Did not detect 2 valid UTF-16 ascii-range characters
    if nullcount == 3:
        if sample[:3] == _null3:
            return 'utf-32-be'
        if sample[1:] == _null3:
            return 'utf-32-le'
        # Did not detect a valid UTF-32 ascii-range character
    return None 

def detectBOM(self):
        """Attempts to detect at BOM at the start of the stream. If
        an encoding can be determined from the BOM return the name of the
        encoding otherwise return None"""
        bomDict = {
            codecs.BOM_UTF8: 'utf-8',
            codecs.BOM_UTF16_LE: 'utf-16le', codecs.BOM_UTF16_BE: 'utf-16be',
            codecs.BOM_UTF32_LE: 'utf-32le', codecs.BOM_UTF32_BE: 'utf-32be'
        }

        # Go to beginning of file and read in 4 bytes
        string = self.rawStream.read(4)
        assert isinstance(string, bytes)

        # Try detecting the BOM using bytes from the string
        encoding = bomDict.get(string[:3])         # UTF-8
        seek = 3
        if not encoding:
            # Need to detect UTF-32 before UTF-16
            encoding = bomDict.get(string)         # UTF-32
            seek = 4
            if not encoding:
                encoding = bomDict.get(string[:2])  # UTF-16
                seek = 2

        # Set the read position past the BOM if one was found, otherwise
        # set it to the start of the stream
        if encoding:
            self.rawStream.seek(seek)
            return lookupEncoding(encoding)
        else:
            self.rawStream.seek(0)
            return None 

def guess_json_utf(data):
    # JSON always starts with two ASCII characters, so detection is as
    # easy as counting the nulls and from their location and count
    # determine the encoding. Also detect a BOM, if present.
    sample = data[:4]
    if sample in (codecs.BOM_UTF32_LE, codecs.BOM32_BE):
        return 'utf-32'     # BOM included
    if sample[:3] == codecs.BOM_UTF8:
        return 'utf-8-sig'  # BOM included, MS style (discouraged)
    if sample[:2] in (codecs.BOM_UTF16_LE, codecs.BOM_UTF16_BE):
        return 'utf-16'     # BOM included
    nullcount = sample.count(_null)
    if nullcount == 0:
        return 'utf-8'
    if nullcount == 2:
        if sample[::2] == _null2:   # 1st and 3rd are null
            return 'utf-16-be'
        if sample[1::2] == _null2:  # 2nd and 4th are null
            return 'utf-16-le'
        # Did not detect 2 valid UTF-16 ascii-range characters
    if nullcount == 3:
        if sample[:3] == _null3:
            return 'utf-32-be'
        if sample[1:] == _null3:
            return 'utf-32-le'
        # Did not detect a valid UTF-32 ascii-range character
    return None 

def encode(input, errors='strict'):
    return (codecs.BOM_UTF8 + codecs.utf_8_encode(input, errors)[0],
            len(input)) 

def guess_json_utf(data):
    """
    :rtype: str
    """
    # JSON always starts with two ASCII characters, so detection is as
    # easy as counting the nulls and from their location and count
    # determine the encoding. Also detect a BOM, if present.
    sample = data[:4]
    if sample in (codecs.BOM_UTF32_LE, codecs.BOM_UTF32_BE):
        return 'utf-32'     # BOM included
    if sample[:3] == codecs.BOM_UTF8:
        return 'utf-8-sig'  # BOM included, MS style (discouraged)
    if sample[:2] in (codecs.BOM_UTF16_LE, codecs.BOM_UTF16_BE):
        return 'utf-16'     # BOM included
    nullcount = sample.count(_null)
    if nullcount == 0:
        return 'utf-8'
    if nullcount == 2:
        if sample[::2] == _null2:   # 1st and 3rd are null
            return 'utf-16-be'
        if sample[1::2] == _null2:  # 2nd and 4th are null
            return 'utf-16-le'
        # Did not detect 2 valid UTF-16 ascii-range characters
    if nullcount == 3:
        if sample[:3] == _null3:
            return 'utf-32-be'
        if sample[1:] == _null3:
            return 'utf-32-le'
        # Did not detect a valid UTF-32 ascii-range character
    return None 

def detectBOM(self):
        """Attempts to detect at BOM at the start of the stream. If
        an encoding can be determined from the BOM return the name of the
        encoding otherwise return None"""
        bomDict = {
            codecs.BOM_UTF8: 'utf-8',
            codecs.BOM_UTF16_LE: 'utf-16le', codecs.BOM_UTF16_BE: 'utf-16be',
            codecs.BOM_UTF32_LE: 'utf-32le', codecs.BOM_UTF32_BE: 'utf-32be'
        }

        # Go to beginning of file and read in 4 bytes
        string = self.rawStream.read(4)
        assert isinstance(string, bytes)

        # Try detecting the BOM using bytes from the string
        encoding = bomDict.get(string[:3])         # UTF-8
        seek = 3
        if not encoding:
            # Need to detect UTF-32 before UTF-16
            encoding = bomDict.get(string)         # UTF-32
            seek = 4
            if not encoding:
                encoding = bomDict.get(string[:2])  # UTF-16
                seek = 2

        # Set the read position past the BOM if one was found, otherwise
        # set it to the start of the stream
        if encoding:
            self.rawStream.seek(seek)
            return lookupEncoding(encoding)
        else:
            self.rawStream.seek(0)
            return None 

def guess_json_utf(data):
    # JSON always starts with two ASCII characters, so detection is as
    # easy as counting the nulls and from their location and count
    # determine the encoding. Also detect a BOM, if present.
    sample = data[:4]
    if sample in (codecs.BOM_UTF32_LE, codecs.BOM32_BE):
        return 'utf-32'     # BOM included
    if sample[:3] == codecs.BOM_UTF8:
        return 'utf-8-sig'  # BOM included, MS style (discouraged)
    if sample[:2] in (codecs.BOM_UTF16_LE, codecs.BOM_UTF16_BE):
        return 'utf-16'     # BOM included
    nullcount = sample.count(_null)
    if nullcount == 0:
        return 'utf-8'
    if nullcount == 2:
        if sample[::2] == _null2:   # 1st and 3rd are null
            return 'utf-16-be'
        if sample[1::2] == _null2:  # 2nd and 4th are null
            return 'utf-16-le'
        # Did not detect 2 valid UTF-16 ascii-range characters
    if nullcount == 3:
        if sample[:3] == _null3:
            return 'utf-32-be'
        if sample[1:] == _null3:
            return 'utf-32-le'
        # Did not detect a valid UTF-32 ascii-range character
    return None 

def guess_json_utf(data):
    # JSON always starts with two ASCII characters, so detection is as
    # easy as counting the nulls and from their location and count
    # determine the encoding. Also detect a BOM, if present.
    sample = data[:4]
    if sample in (codecs.BOM_UTF32_LE, codecs.BOM32_BE):
        return 'utf-32'     # BOM included
    if sample[:3] == codecs.BOM_UTF8:
        return 'utf-8-sig'  # BOM included, MS style (discouraged)
    if sample[:2] in (codecs.BOM_UTF16_LE, codecs.BOM_UTF16_BE):
        return 'utf-16'     # BOM included
    nullcount = sample.count(_null)
    if nullcount == 0:
        return 'utf-8'
    if nullcount == 2:
        if sample[::2] == _null2:   # 1st and 3rd are null
            return 'utf-16-be'
        if sample[1::2] == _null2:  # 2nd and 4th are null
            return 'utf-16-le'
        # Did not detect 2 valid UTF-16 ascii-range characters
    if nullcount == 3:
        if sample[:3] == _null3:
            return 'utf-32-be'
        if sample[1:] == _null3:
            return 'utf-32-le'
        # Did not detect a valid UTF-32 ascii-range character
    return None 

def _buffer_decode(self, input, errors, final):
        if self.first:
            if len(input) < 3:
                if codecs.BOM_UTF8.startswith(input):
                    # not enough data to decide if this really is a BOM
                    # => try again on the next call
                    return (u"", 0)
                else:
                    self.first = None
            else:
                self.first = None
                if input[:3] == codecs.BOM_UTF8:
                    (output, consumed) = codecs.utf_8_decode(input[3:], errors, final)
                    return (output, consumed+3)
        return codecs.utf_8_decode(input, errors, final) 

def encode(self, input, final=False):
        if self.first:
            self.first = 0
            return codecs.BOM_UTF8 + codecs.utf_8_encode(input, self.errors)[0]
        else:
            return codecs.utf_8_encode(input, self.errors)[0] 

def decode(input, errors='strict'):
    prefix = 0
    if input[:3] == codecs.BOM_UTF8:
        input = input[3:]
        prefix = 3
    (output, consumed) = codecs.utf_8_decode(input, errors, True)
    return (output, consumed+prefix) 

def encode(input, errors='strict'):
    return (codecs.BOM_UTF8 + codecs.utf_8_encode(input, errors)[0], len(input)) 

def test_bom(self):
        fn = os.path.join(TEST_DATA_DIR, "bom.py")
        data = self.check_file_refactoring(fn)
        self.assertTrue(data.startswith(codecs.BOM_UTF8)) 

def detectBOM(self):
        """Attempts to detect at BOM at the start of the stream. If
        an encoding can be determined from the BOM return the name of the
        encoding otherwise return None"""
        bomDict = {
            codecs.BOM_UTF8: 'utf-8',
            codecs.BOM_UTF16_LE: 'utf-16-le', codecs.BOM_UTF16_BE: 'utf-16-be',
            codecs.BOM_UTF32_LE: 'utf-32-le', codecs.BOM_UTF32_BE: 'utf-32-be'
        }

        # Go to beginning of file and read in 4 bytes
        string = self.rawStream.read(4)
        assert isinstance(string, bytes)

        # Try detecting the BOM using bytes from the string
        encoding = bomDict.get(string[:3])         # UTF-8
        seek = 3
        if not encoding:
            # Need to detect UTF-32 before UTF-16
            encoding = bomDict.get(string)         # UTF-32
            seek = 4
            if not encoding:
                encoding = bomDict.get(string[:2])  # UTF-16
                seek = 2

        # Set the read position past the BOM if one was found, otherwise
        # set it to the start of the stream
        self.rawStream.seek(encoding and seek or 0)

        return encoding 

def guess_json_utf(data):
    """
    :rtype: str
    """
    # JSON always starts with two ASCII characters, so detection is as
    # easy as counting the nulls and from their location and count
    # determine the encoding. Also detect a BOM, if present.
    sample = data[:4]
    if sample in (codecs.BOM_UTF32_LE, codecs.BOM_UTF32_BE):
        return 'utf-32'     # BOM included
    if sample[:3] == codecs.BOM_UTF8:
        return 'utf-8-sig'  # BOM included, MS style (discouraged)
    if sample[:2] in (codecs.BOM_UTF16_LE, codecs.BOM_UTF16_BE):
        return 'utf-16'     # BOM included
    nullcount = sample.count(_null)
    if nullcount == 0:
        return 'utf-8'
    if nullcount == 2:
        if sample[::2] == _null2:   # 1st and 3rd are null
            return 'utf-16-be'
        if sample[1::2] == _null2:  # 2nd and 4th are null
            return 'utf-16-le'
        # Did not detect 2 valid UTF-16 ascii-range characters
    if nullcount == 3:
        if sample[:3] == _null3:
            return 'utf-32-be'
        if sample[1:] == _null3:
            return 'utf-32-le'
        # Did not detect a valid UTF-32 ascii-range character
    return None