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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_openbus(self, service, endpoint, **kwargs):
 """Make a request to the given endpoint of the ``openbus`` server. This returns the plain JSON (dict) response which can then be parsed using one of the implemented types. Args: service (str):
 Service to fetch ('bus' or 'geo'). endpoint (str):
 Endpoint to send the request to. This string corresponds to the key in the ``ENDPOINTS`` dict. **kwargs: Request arguments. Returns: Obtained response (dict) or None if the endpoint was not found. """

        if service == 'bus':
            endpoints = ENDPOINTS_BUS

        elif service == 'geo':
            endpoints = ENDPOINTS_GEO

        else:
            # Unknown service
            return None

        if endpoint not in endpoints:
            # Unknown endpoint
            return None

        url = URL_OPENBUS + endpoints[endpoint]

        # Append credentials to request
        kwargs['idClient'] = self._emt_id
        kwargs['passKey'] = self._emt_pass

        # SSL verification fails...
        # return requests.post(url, data=kwargs, verify=False).json()
        return requests.post(url, data=kwargs, verify=True).json()