Hello @shliao
GPIO36 does not support internal software pull-ups. So if your hardware setup requires a pull-up, you'll need to add an external pull-up resistor.
Excerpt from this documentation:
GPIO34-39 can only be set as input mode and do not have software pullup or pulldown functions.
BTW: your Python code is ok and returns 1 when I connect GPIO36 to 3.3 V.
Thanks
Felix