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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 alias(self, v, stat='dummy'):
 """Return a representation of a value suitable for use in historical queries. It will behave much as if you assigned the value to some entity and then used its ``historical`` method to get a reference to the set of its past values, which happens to contain only the value you've provided here, ``v``. :arg v: the value to represent :arg stat: what name to pretend its stat has; usually irrelevant """

        from .util import EntityStatAccessor
        r = DummyEntity(self)
        r[stat] = v
        return EntityStatAccessor(r, stat, engine=self)