      def check_display():
          """ Check whether there is a display to output the GUI. If running on
              Windows then assume not running in headless mode """
          if not os.environ.get("DISPLAY", None) and os.name != "nt":
              logger.warning("No display detected. GUI mode has been disabled.")
              if platform.system() == "Darwin":
                  logger.info("macOS users need to install XQuartz. "
                              "See https://support.apple.com/en-gb/HT201341")
              exit(1)
  
 
</s> remove             exit(1)
 </s> add             raise FaceswapError("No display detected. GUI mode has been disabled.") </s> remove             exit(1)
 </s> add             raise FaceswapError("TkInter not found") </s> remove             logger.error("The maximumum supported Tensorflow is version %s but you have version "
                         "%s installed. Please downgrade Tensorflow.", max_ver, tf_ver)
            exit(1)
 </s> add             raise FaceswapError("The maximumum supported Tensorflow is version {} but you have "
                                "version {} installed. Please downgrade Tensorflow.".format(
                                    max_ver, tf_ver)) </s> remove             logger.error("Tensorflow is a requirement but is not installed on your system.")
            exit(1)
 </s> add             raise FaceswapError("Tensorflow is a requirement but is not installed on your system.")
      def check_display():
          """ Check whether there is a display to output the GUI. If running on
              Windows then assume not running in headless mode """
          if not os.environ.get("DISPLAY", None) and os.name != "nt":

              if platform.system() == "Darwin":
                  logger.info("macOS users need to install XQuartz. "
                              "See https://support.apple.com/en-gb/HT201341")
              exit(1)
  
keep keep keep keep replace keep keep keep keep keep
 FaceswapError Exception. Added to cli and utils 
lib/cli.py