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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 request_parking(self, endpoint, url_args={}, **kwargs):
 """Make a request to the given endpoint of the ``parking`` server. This returns the plain JSON (dict) response which can then be parsed using one of the implemented types. Args: endpoint (str):
 Endpoint to send the request to. This string corresponds to the key in the ``ENDPOINTS`` dict. url_args (dict):
 Dictionary for URL string replacements. **kwargs: Request arguments. Returns: Obtained response (dict) or None if the endpoint was not found. """

        if endpoint not in ENDPOINTS_PARKING:
            # Unknown endpoint
            return None

        url = URL_OPENBUS + ENDPOINTS_PARKING[endpoint]

        # Append additional info to URL
        lang = url_args.get('lang', 'ES')
        address = url_args.get('address', '')

        url = url.format(
            id_client=self._emt_id,
            passkey=self._emt_pass,
            address=address,
            lang=lang
        )

        # This server uses TLSv1
        return _parking_req.post(url, data=kwargs).json()