code: def neutralize_main(self, path, src):
          
          match = self.MAIN_RE.search(src)
          if match:
              return src[:match.start()]
  
          if b('mitogen.main(') in src:
              return src
  
          LOG.error(self.main_guard_msg, path)
          raise ImportError('refused')
docs: Given the source for the __main__ module, try to find where it
          begins conditional execution based on a "if __name__ == '__main__'"
          guard, and remove any code after that point.