<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _get_json(self, url):
 """ Get json from url """

        self.log.info(u"/GET " + url)
        r = requests.get(url)
        if hasattr(r, 'from_cache'):
            if r.from_cache:
                self.log.info("(from cache)")
        if r.status_code != 200:
            throw_request_err(r)

        return r.json()