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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 encrypt(self, key):
 """This method encrypts and signs the state to make it unreadable by the server, since it contains information that would allow faking proof of storage. :param key: the key to encrypt and sign with """

        if (self.encrypted):
            return
        # encrypt
        self.iv = Random.new().read(AES.block_size)
        aes = AES.new(key, AES.MODE_CFB, self.iv)
        self.f_key = aes.encrypt(self.f_key)
        self.alpha_key = aes.encrypt(self.alpha_key)
        self.encrypted = True
        # sign
        self.hmac = self.get_hmac(key)