Ошибка при запуске Django, сразу после создания проекта

$ ./manage.py     
Traceback (most recent call last):
 File "./manage.py", line 17, in <module>
   "Couldn't import Django. Are you sure it's installed and "
ImportError: Couldn't import Django. Are you sure it's installed and available on your PYTHONPATH environment variable? Di
d you forget to activate a virtual environment?