[terminal]关于进度条的学习

 1 @contextlib.contextmanager
 2 def hidden_cursor(file):
 3     # The Windows terminal does not support the hide/show cursor ANSI codes,
 4     # even via colorama. So don‘t even try.
 5     if WINDOWS:
 6         yield
 7     # We don‘t want to clutter the output with control characters if we‘re
 8     # writing to a file, or if the user is running with --quiet.
 9     # See https://github.com/pypa/pip/issues/3418
10     elif not file.isatty() or logger.getEffectiveLevel() > logging.INFO:
11         yield
12     else:
13         file.write(HIDE_CURSOR)
14         try:
15             yield
16         finally:
17             file.write(SHOW_CURSOR)

1 HIDE_CURSOR = ‘\x1b[?25l‘
2 SHOW_CURSOR = ‘\x1b[?25h‘