main part of this proposal.
Clears all characters from the cursor to the end of the line. That lets us make sure that when we delete and re-print a shorter input after that, any "leftover" text that we're not over-writing still gets properly cleared from the screen.，更多细节参见体育直播
ITmedia�̓A�C�e�B���f�B�A�������Ђ̓o�^���W�ł��B，这一点在体育直播中也有详细论述
def command_line():。体育直播是该领域的重要参考