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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 generate_key(block_size=32):
 """Generate random key for ope cipher. Parameters block_size : int, optional Length of random bytes. Returns ------- random_key : str A random key for encryption. Notes: ------ Implementation follows https://github.com/pyca/cryptography """

        random_seq = os.urandom(block_size)
        random_key = base64.b64encode(random_seq)
        return random_key