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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def mongoqs_to_json(qs, fields=None):
 """ transform mongoengine.QuerySet to json """


    l = list(qs.as_pymongo())

    for element in l:
        element.pop('_cls')

    # use DjangoJSONEncoder for transform date data type to datetime
    json_qs = json.dumps(l, indent=2, ensure_ascii=False, cls=DjangoJSONEncoder)
    return json_qs