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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 evaluate(self):
 """Get the result of evaluating the computation graph at this node."""

        if DEVELOP:
            internal_assert(not self.been_called, "inefficient reevaluation of action " + self.name + " with tokens", self.tokens)
            self.been_called = True
        evaluated_toks = evaluate_tokens(self.tokens)
        if logger.tracing:  # avoid the overhead of the call if not tracing
            logger.log_trace(self.name, self.original, self.loc, evaluated_toks, self.tokens)
        try:
            return _trim_arity(self.action)(
                self.original,
                self.loc,
                evaluated_toks,
            )
        except CoconutException:
            raise
        except (Exception, AssertionError):
            traceback.print_exc()
            raise CoconutInternalException("error computing action " + self.name + " of evaluated tokens", evaluated_toks)