Make a get request against the charmstore.

        This method is used by other API methods to standardize querying.
        @param url The full url to query
            (e.g. https://api.jujucharms.com/charmstore/v4/macaroon)

def _get(self, url):
        """Make a get request against the charmstore.

        This method is used by other API methods to standardize querying.
        @param url The full url to query
            (e.g. https://api.jujucharms.com/charmstore/v4/macaroon)
        """
        try:
            response = requests.get(url, verify=self.verify,
                                    cookies=self.cookies, timeout=self.timeout,
                                    auth=self._client.auth())
            response.raise_for_status()
            return response
        except HTTPError as exc:
            if exc.response.status_code in (404, 407):
                raise EntityNotFound(url)
            else:
                message = ('Error during request: {url} '
                           'status code:({code}) '
                           'message: {message}').format(
                               url=url,
                               code=exc.response.status_code,
                               message=exc.response.text)
                logging.error(message)
                raise ServerError(exc.response.status_code,
                                  exc.response.text,
                                  message)
        except Timeout:
            message = 'Request timed out: {url} timeout: {timeout}'
            message = message.format(url=url, timeout=self.timeout)
            logging.error(message)
            raise ServerError(message)
        except RequestException as exc:
            message = ('Error during request: {url} '
                       'message: {message}').format(
                           url=url,
                           message=exc)
            logging.error(message)
            raise ServerError(exc.args[0][1].errno,
                              exc.args[0][1].strerror,
                              message)