def _convert_signed_hex(s):
if s.startswith('<STR_LIT>') or s.startswith('<STR_LIT>'):<EOL><INDENT>s = '<STR_LIT>'.format(struct.unpack('<STR_LIT>', struct.pack('<STR_LIT:q>', int(s, <NUM_LIT:16>)))[<NUM_LIT:0>])<EOL><DEDENT>return s.zfill(<NUM_LIT:16>)<EOL>
Takes a signed hex string that begins with '0x' and converts it to
    a 16-character string representing an unsigned hex value.
    Examples:
        '0xd68adf75f4cfd13' => 'd68adf75f4cfd13'
        '-0x3ab5151d76fb85e1' => 'c54aeae289047a1f'