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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 getCiphertextLen(self, ciphertext):
 """Given a ``ciphertext`` with a valid header, returns the length of the ciphertext inclusive of ciphertext expansion. """


        plaintext_length = self.getPlaintextLen(ciphertext)
        ciphertext_length = plaintext_length + Encrypter._CTXT_EXPANSION
        return ciphertext_length