code: def injected(self, filename):
          
          full_path = os.path.expanduser(filename)
          if not os.path.exists(full_path):
              return False
          with codecs.open(full_path, 'r+', encoding="utf-8") as fh:
              contents = fh.read()
          return self.wrapper_match.search(contents) is not None
docs: Return true if the file has already been injected before.