<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(cls, *args, **kwargs):
 """ Same as collection.find, but return Document then dict """

        for doc in cls._coll.find(*args, **kwargs):
            yield cls.from_storage(doc)