I wanna add a new function named `clear` to the os module.
This function runs the `clear` command in the os.
but this function checks that is os windows, if yes, runs `cls`.
I'm working on my patch.

The idea of adding some kind of clear_screen() function in the os or shutil module was discussed extensively on python-ideas a few months ago:

https://mail.python.org/archives/list/python-ideas@python.org/thread/EWQ2BOL3WVZAU2V2MT3HLXN3AEBHANNZ
https://mail.python.org/archives/list/python-ideas@python.org/thread/N2G5MDPST6IMUQCK6LLAUOVIJIOOC2XJ

I would not want to clear the terminal scrollback buffer, in which case the implementation in Windows would need to use the console API and/or VT sequences instead of the CMD shell's CLS command.

Well, some times we are writing a flexible Text ui program. we may use `clear` lot of times. This should be used when we haven't any valuable data on the screen. Also, who that uses this function, knows this will clear valuable data :). Sometimes also i use this command. but every time a should check that is this operation windows or not, to determine `clear` or `cls`. I think this is very helpful for making this easier.
The best feature of Python is its simplicity and power. More helper functions to make the code shorter and knowable, is a good thing for Python. Also about the Windows API instead of `cls`, i don't know more thing. But i think its not a big problem and `cls` works.

If you write a flexible Text ui program, you should use functions provided by a text ui library which you use to clear the screen or a part of screen.

If you want to call an external command, use os.system(), os.popen() or more flexible subprocess module. But I do not think it will help with Text UI.