Python - Hex

XOR

xor(a, b) # Same as a ^ b.

char <-> int

i  = ord (c)
c = chr(i)

def dec2hex(n):
  # n is integer!
  return "%X" % n

def hex2dec(s):
  # s is string!
  return int(s, 16)

print dec2hex(255) # FF
print hex2dec('FF') # 255
print hex(255) # 0xff
print hex2dec('0xff') # 255