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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _write(self, f):
 """Serialize an NDEF record to a file-like object."""

        log.debug("writing ndef record at offset {0}".format(f.tell()))

        record_type = self.type
        record_name = self.name
        record_data = self.data
        
        if record_type == '':
            header_flags = 0; record_name = ''; record_data = ''
        elif record_type.startswith("urn:nfc:wkt:"):
            header_flags = 1; record_type = record_type[12:]
        elif re.match(r'[a-zA-Z0-9-]+/[a-zA-Z0-9-+.]+', record_type):
            header_flags = 2; record_type = record_type
        elif re.match(r'[a-zA-Z][a-zA-Z0-9+-.]*://', record_type):
            header_flags = 3; record_type = record_type
        elif record_type.startswith("urn:nfc:ext:"):
            header_flags = 4; record_type = record_type[12:]
        elif record_type == 'unknown':
            header_flags = 5; record_type = ''
        elif record_type == 'unchanged':
            header_flags = 6; record_type = ''

        type_length = len(record_type)
        data_length = len(record_data)
        name_length = len(record_name)

        if self._message_begin:
            header_flags |= 0x80
        if self._message_end:
            header_flags |= 0x40
        if data_length < 256:
            header_flags |= 0x10
        if name_length > 0:
            header_flags |= 0x08

        if data_length < 256:
            f.write(struct.pack(">BBB", header_flags, type_length, data_length))
        else:
            f.write(struct.pack(">BBL", header_flags, type_length, data_length))
        if name_length > 0:
            f.write(struct.pack(">B", name_length))

        f.write(record_type)
        f.write(record_name)
        f.write(record_data)