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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 env(self, current_scope):
 """Return an environment that will look up in current_scope for keys in this tuple, and the parent env otherwise. """

    return self.__env_cache.get(
            current_scope.ident,
            framework.Environment, current_scope,
            names=self.keys(),
            parent=framework.Environment({'self': current_scope}, parent=self.__parent_env))