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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 _create_cipher(self, password, salt, IV):
 """ Create the cipher object to encrypt or decrypt a payload. """

        from Crypto.Protocol.KDF import PBKDF2
        from Crypto.Cipher import AES
        pw = PBKDF2(password, salt, dkLen=self.block_size)
        return AES.new(pw[:self.block_size], AES.MODE_CFB, IV)