Caisar Cipher Python

CaisarCipher___init__.py

from CaisarCipher import CaisarCipher

print CaisarCipher('landika').encode(1)
print CaisarCipher(CaisarCipher('landika').encode(1)).decode(1)

CaisarCipher_CaisarCipher.py

class CaisarCipher:
 def __init__(self, plain):
  self.plain = plain

 def encode(self, key):
  cipher = ''
  for c in self.plain:
   decimalstring = self.hexToDecimal(self.charToHex (c))
   decimalstring = ( decimalstring + key ) % 256
   cipher = cipher + self.hexToChar(self.decimalToHex(decimalstring))
  return cipher

 def decode(self, key):
  self.cipher = self.plain
  plain = ''
  for c in self.cipher:
   decimalstring =  self.hexToDecimal(self.charToHex (c))
   decimalstring = (decimalstring - key) % 256
   plain = plain + self.hexToChar(self.decimalToHex(decimalstring))
  return plain

 def hexToDecimal(self, p1):
  return int(p1, 16)

 def charToHex(self, p1):
  return p1.encode('hex')

 def decimalToHex(self, p1):
  return hex(p1).split('x')[-1]

 def hexToChar(self, p1):
  return p1.decode('hex')