python2 and python3.5, are already included under ubuntu. I installed 3.6 myself, so I chose 3.6 to configure the interpreter under pycharm, but did not actually execute python3.6. For example, if I execute python on the command line, the default is 3.6.3, but if I execute python manage.py runserver (a sentence for launching a web page), it will tell me that django is not installed, but if I execute python3.6 manage.py runserver, it can be executed. This is fine on the command line, so how to set it up under pycharm?