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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 get(self, key=None, **kwargs):
 """ Ensures that only one result is returned from DB and raises an exception otherwise. Can work in 3 different way. - If no argument is given, only does "ensuring about one and only object" job. - If key given as only argument, retrieves the object from DB. - if query filters given, implicitly calls filter() method. Raises: MultipleObjectsReturned: If there is more than one (1) record is returned. """

        clone = copy.deepcopy(self)
        # If we are in a slice, adjust the start and rows
        if self._start:
            clone.adapter.set_params(start=self._start)
        if self._rows:
            clone.adapter.set_params(rows=self._rows)
        if key:
            data, key = clone.adapter.get(key)
        elif kwargs:
            data, key = clone.filter(**kwargs).adapter.get()
        else:
            data, key = clone.adapter.get()
        if clone._cfg['rtype'] == ReturnType.Object:
            return data, key
        return self._make_model(data, key)