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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _pad(self, b):
 """ Will padd the param to be of the correct length for the encryption alg. :type b: bytes :rtype: bytes """

        return b + (self.bs - len(b) % self.bs) * chr(self.bs - len(b) % self.bs).encode("UTF-8")