code: def CPP_to_Python(s):
      
      s = CPP_to_Python_Ops_Expression.sub(CPP_to_Python_Ops_Sub, s)
      for expr, repl in CPP_to_Python_Eval_List:
          s = expr.sub(repl, s)
      return s
docs: Converts a C pre-processor expression into an equivalent
      Python expression that can be evaluated.