How to use the tinytag.tinytag.ID3.FRAME_ID_TO_FIELD.get function in tinytag

bits_per_byte = 7 if id3version == 4 else 8  # only id3v2.4 is synchsafe
        frame_header_data = fh.read(frame_header_size)
        if len(frame_header_data) != frame_header_size:
            return 0
        frame = struct.unpack(binformat, frame_header_data)
        frame_id = self._decode_string(frame[0])
        frame_size = self._calc_size(frame[1:1+frame_size_bytes], bits_per_byte)
        if DEBUG:
            stderr('Found id3 Frame %s at %d-%d of %d' % (frame_id, fh.tell(), fh.tell() + frame_size, self.filesize))
        if frame_size > 0:
            # flags = frame[1+frame_size_bytes:] # dont care about flags.
            if frame_id not in ID3.PARSABLE_FRAME_IDS:  # jump over unparsable frames
                fh.seek(frame_size, os.SEEK_CUR)
                return frame_size
            content = fh.read(frame_size)
            fieldname = ID3.FRAME_ID_TO_FIELD.get(frame_id)
            if fieldname:
                transfunc = self._decode_comment if fieldname == 'comment' else self._decode_string
                self._set_field(fieldname, content, transfunc)
            elif frame_id in self.IMAGE_FRAME_IDS and self._load_image:
                # See section 4.14: http://id3.org/id3v2.4.0-frames
                if frame_id == 'PIC':  # ID3 v2.2:
                    desc_end_pos = content.index(b'\x00', 1) + 1
                else:  # ID3 v2.3+
                    mimetype_end_pos = content.index(b'\x00', 1) + 1
                    desc_start_pos = mimetype_end_pos + 1  # jump over picture type
                    desc_end_pos = content.index(b'\x00', desc_start_pos) + 1
                if content[desc_end_pos:desc_end_pos+1] == b'\x00':
                    desc_end_pos += 1  # the description ends with 1 or 2 null bytes
                self._image_data = content[desc_end_pos:]
            return frame_size
        return 0