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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 DecryptPrivateKey(self, encrypted_private_key):
 """ Decrypt the provided ciphertext with the initialized private key. Args: encrypted_private_key (byte string):
 the ciphertext to be decrypted. Returns: bytes: the ciphertext. """

        aes = AES.new(self._master_key, AES.MODE_CBC, self._iv)
        return aes.decrypt(encrypted_private_key)