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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 compute_accept_value(key: Union[str, bytes]) -> str: """Computes the value for the Sec-WebSocket-Accept header, given the value for Sec-WebSocket-Key. """

        sha1 = hashlib.sha1()
        sha1.update(utf8(key))
        sha1.update(b"258EAFA5-E914-47DA-95CA-C5AB0DC85B11")  # Magic value
        return native_str(base64.b64encode(sha1.digest()))