<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def query_trial(request):
 """Rest API to query the trial info, with the given trial_id. The url pattern should be like this: curl http://<server>:<port>/query_trial?trial_id=<trial_id> The response may be: { "app_url": "None", "trial_status": "TERMINATED", "params": {'a': 1, 'b': 2}, "job_id": "asynchyperband_test", "end_time": "2018-07-19 20:49:44", "start_time": "2018-07-19 20:49:40", "trial_id": "2067R2ZD", } """

    trial_id = request.GET.get("trial_id")
    trials = TrialRecord.objects \
        .filter(trial_id=trial_id) \
        .order_by("-start_time")
    if len(trials) == 0:
        resp = "Unkonwn trial id %s.\n" % trials
    else:
        trial = trials[0]
        result = {
            "trial_id": trial.trial_id,
            "job_id": trial.job_id,
            "trial_status": trial.trial_status,
            "start_time": trial.start_time,
            "end_time": trial.end_time,
            "params": trial.params
        }
        resp = json.dumps(result)
    return HttpResponse(resp, content_type="application/json;charset=utf-8")