Switch to or open a process in the background - python

Question

Hillo When the user clicks on the program icon, there is a code that checks whether the program is running in the background or not, if the condition is met, the switch to or open this background process, or the program opens again if it was not running before (I have a problem because it opens more than once in the taskbar)

def process():
    import psutil
    PROCNAME = 'test.exe'
    for proc in psutil.process_iter():
        try:
            if proc.name().lower() == PROCNAME.lower():
                return
        except (psutil.NoSuchProcess, psutil.AccessDenied, psutil.ZombieProcess):
            pass
    MainThred = QApplication([])
    MainGUI = MainWindow()
    MainGUI.show()
    sysExit(MainThred.exec_())
if __name__ == "__main__":
    process()

Answer 1

等待大神答复