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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 close(self, code: int = None, reason: str = None) -> None: """Closes this Web Socket. Once the close handshake is successful the socket will be closed. ``code`` may be a numeric status code, taken from the values defined in `RFC 6455 section 7.4.1 <https://tools.ietf.org/html/rfc6455#section-7.4.1>`_. ``reason`` may be a textual message about why the connection is closing. These values are made available to the client, but are not otherwise interpreted by the websocket protocol. .. versionchanged:: 4.0 Added the ``code`` and ``reason`` arguments. """

        if self.ws_connection:
            self.ws_connection.close(code, reason)
            self.ws_connection = None