code: def sub(self, s):
      for k, v in self.macros.items():
          s = s.replace(k, v)
      return s
  
imports: import os
  import subprocess
  import sys
  import re
  from distutils.errors import DistutilsExecError, DistutilsPlatformError, CompileError, LibError, LinkError
  from distutils.ccompiler import CCompiler, gen_lib_options
  from distutils import log
  from distutils.util import get_platform
  import winreg
label_desc: Use image node_id 4 for calling the MacroExpander obj's underlying member method code with example usage: obj.sub(s) and returns: s