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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 substitute(self, values={}, functions={}):
 """Evaluate the template given the values and functions. """

        try:
            res = self.compiled(values, functions)
        except Exception:  # Handle any exceptions thrown by compiled version.
            res = self.interpret(values, functions)

        return res