code: def get(self, key):
          
          query = self._conn.execute("SELECT * FROM cache WHERE key=?", (key,))
          rec = query.fetchone()
          if rec is None:
              return None
          rec = dict(zip(self._columns, rec))
  
          if self.check_last_modified:
              if rec['modified'] is None:
                  return None  # no last modified header present, so redownload
  
              head_resp = requests.head(key)
              new_lm = head_resp.headers.get('last-modified', None)
              if rec['modified'] != new_lm:
                  return None
  
          resp = requests.Response()
          resp._content = rec['data']
          resp.status_code = rec['status']
          resp.encoding = rec['encoding']
          resp.headers = json.loads(rec['headers'])
          resp.url = key
          return resp
docs: Get cache entry for key, or return None.