input.py 文件源码

def __init__(self, stdin=None):
        self.stdin = stdin or sys.stdin

        # The input object should be a TTY.
        assert self.stdin.isatty()

        # Test whether the given input object has a file descriptor.
        # (Idle reports stdin to be a TTY, but fileno() is not implemented.)
        try:
            # This should not raise, but can return 0.
            self.stdin.fileno()
        except io.UnsupportedOperation:
            if 'idlelib.run' in sys.modules:
                raise io.UnsupportedOperation(
                    'Stdin is not a terminal. Running from Idle is not supported.')
            else:
                raise io.UnsupportedOperation('Stdin is not a terminal.')