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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 _req(self, endpoint, get_data=dict(), post_data=dict()):
 """Helper method to make API calls :param endpoint: The endpoint to make the API call to :param get_data: data send through GET :param post_data: data send through POST """


        if get_data:
            request_parameter = "{}?{}".format(endpoint, urlencode(get_data))
        else:
            request_parameter = endpoint

        try:
            encdata = urlencode(post_data, True).encode('utf-8')
            response = self.oauth.request(request_parameter, data=encdata)
            self._checkResponseForErrors(response)
        except HTTPError as e:
            raise DeviantartError(e)

        return response