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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 eval_expression(self, t):
 """ Evaluates a C preprocessor expression. This is done by converting it to a Python equivalent and eval()ing it in the C preprocessor namespace we use to track #define values. """

        t = CPP_to_Python(' '.join(t[1:]))
        try: return eval(t, self.cpp_namespace)
        except (NameError, TypeError): return 0