обновлено с ubuntu 18.04 до 20.04, и теперь мой проект django не работает

когда я активирую свою виртуальную среду и ввожу python manage.py runserver , это дает мне следующую ошибку:

(myenv) nouman@nouman-G3:~/Documents/test/myshop$ python manage.py runserver
Traceback (most recent call last):
  File "manage.py", line 10, in main
    from django.core.management import execute_from_command_line
ModuleNotFoundError: No module named 'django'

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "manage.py", line 21, in <module>
    main()
  File "manage.py", line 12, in main
    raise ImportError(
ImportError: Couldn't import Django. Are you sure it's installed and available on your PYTHONPATH environment variable? Did you forget to activate a virtual environment?

Я даже пробовал с 'python3', но все равно не работает