In python code, you can use sys.path to add or modify the path of the package, but such an operation will cause the code prompt to fail in pycharm.
In order to solve the code prompt of pycharm, you need to modify the configuration of pycharm, as follows, the version is pycharm2018.1:
The first step is to open the settings, find the project settings, click the gear icon in the figure below, and select Show All in the drop-down menu.
The second step, click the icon in the figure below to pop up the current path
The third step, add or modify the path yourself
Finally, remember to restart pycharm