python怎么判断进程是否杀掉？

import win32com.client

def check_exsit(process_name):

    WMI = win32com.client.GetObject('winmgmts:')

    processCodeCov = WMI.ExecQuery('select * from Win32_Process where Name like "%{}%"'.format(process_name))

    if len(processCodeCov) > 0:

        return True

    else:

        return False

if __name__ == '__main__':

    res = check_exsit('tray.exe')

    print(res)