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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_base64encoded_randomness(num_bytes: int) -> str: """ Create and return ``num_bytes`` of random data. The result is encoded in a string with URL-safe ``base64`` encoding. Used (for example) to generate session tokens. Which generator to use? See https://cryptography.io/en/latest/random-numbers/. Do NOT use these methods: .. code-block:: python randbytes = M2Crypto.m2.rand_bytes(num_bytes) # NO! randbytes = Crypto.Random.get_random_bytes(num_bytes) # NO! Instead, do this: .. code-block:: python randbytes = os.urandom(num_bytes) # YES """

    randbytes = os.urandom(num_bytes)  # YES
    return base64.urlsafe_b64encode(randbytes).decode('ascii')