bytearray to hexpairs string

printable_diff_out = ''.join('{:02x} '.format(x) for x in diff_out)

[ecomaikgolf@desktop ../faults/03_aes/]$ ./exploit.py
Input  differential: bytearray(b'\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01')
Output differential: bytearray(b'"\x00\x00\x00\xdf\x00\x00\x00\xfc\x00\x00\x00\xb3\x00\x00\x00')

[ecomaikgolf@desktop ../faults/03_aes/]$ ./exploit.py
Input  differential: 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01
Output differential: 22 00 00 00 df 00 00 00 fc 00 00 00 b3 00 00 00