def __init__(self, model_class=None, keys_only=False, cursor=None,
               namespace=None, _app=None, distinct=False, projection=None):
    super(Query, self).__init__(model_class)

    if keys_only:
      self._keys_only = True
    if projection:
      self._projection = projection
    if namespace is not None:
      self._namespace = namespace
    if _app is not None:
      self._app = _app
    if distinct:
      self._distinct = True

    self.__query_sets = [{}]
    self.__orderings = []
    self.with_cursor(cursor)
Constructs a query over instances of the given Model.
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/ext/db/__init__.py/Query.__init__