code: def ensure_echo_on():
      
      # tcgetattr will fail if stdin isn't a tty
      if not sys.stdin.isatty():
          return
      try:
          import termios
      except ImportError:
          return
      attributes = termios.tcgetattr(sys.stdin)
      if not attributes[3] & termios.ECHO:
          attributes[3] |= termios.ECHO
          termios.tcsetattr(sys.stdin, termios.TCSANOW, attributes)
docs: Ensure that echo mode is enabled. Some tools such as PDB disable
      it which causes usability issues after reload.