@staticmethod<EOL><INDENT>def pack_chunk(tag, data):<DEDENT>
to_check = tag + data<EOL>return (struct.pack(b"<STR_LIT>", len(data)) + to_check +<EOL>struct.pack(b"<STR_LIT>", zlib.crc32(to_check) & <NUM_LIT>))<EOL>
Pack a PNG chunk for serializing to disk