Perform an HTTP Request using base_url and parameters
        given by kwargs.
        Results are expected to be given in JSON format
        and are parsed to python data structures.

def _http_request(self, service_type, **kwargs):
        """
        Perform an HTTP Request using base_url and parameters
        given by kwargs.
        Results are expected to be given in JSON format
        and are parsed to python data structures.
        """
        request_params = urlencode(kwargs)
        request_params = request_params.replace('%28', '').replace('%29', '')

        uri = '%s%s?api_key=%s&%s' % \
            (self.base_url, service_type, self.api_key, request_params)
        header, response = self.conn.request(uri, method='GET')
        return header, response