python执行Linux命令

def exe_cmd(cmd):
    p = subprocess.Popen(cmd, shell=True, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
    while True:
        next_line = p.stdout.readline()
        return_line = next_line.decode("utf-8", "ignore")
        if return_line == ‘‘ and p.poll() != None:
            break
        print(return_line)
    stdout, stderr = p.communicate()
    if p.returncode != 0:
        return False
    return True