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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_vars(self):
 """ Returns a complete dict of all variables that are defined in this scope, including the variables of the parent. """

        if self.parent is None:
            vars = {}
            vars.update(self.variables)
            return vars
        vars = self.parent.get_vars()
        vars.update(self.variables)
        return vars