code: def get_napp(self, username, name):
          
          endpoint = os.path.join(self._config.get('napps', 'api'), 'napps',
                                  username, name, '')
          res = self.make_request(endpoint)
          if res.status_code == 404:  # We need to know if NApp is not found
              return None
          if res.status_code != 200:
              msg = 'Error getting %s/%s from server: (%d) - %s'
              raise KytosException(msg % (username, name, res.status_code,
                                          res.reason))
          return json.loads(res.content)
docs: Return napp metadata or None if not found.