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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 features(self, map_id, feature_format="json"):
 """Returns vector features from Mapbox Editor projects as GeoJSON or KML. Parameters map_id : str The map's unique identifier in the format username.id. feature_format : str, optional The vector's feature format. The default value is json. Returns ------- request.Response The response object with vector features. """


        # Validate feature_format.

        feature_format = self._validate_feature_format(feature_format)
   
        # Create dict to assist in building URI resource path.

        path_values = dict(
            map_id=map_id,
            feature_format=feature_format
        )

        # Build URI resource path.

        path_part = "/{map_id}/features.{feature_format}"
        uri = URITemplate(self.base_uri + path_part).expand(**path_values)

        # Send HTTP GET request.

        response = self.session.get(uri)
        self.handle_http_error(response)

        return response