[Answered ]-List & tuple aren't working despite addressing `django.core.excptions.ImproperlyConfigured: The TEMPLATE_DIRS setting must be a list or a tuple` error

TEMPLATE_DIRS is already a list, so it makes no sense to wrap that again in the list, you should define the TEMPLATES setting as:

TEMPLATES = [
    {
        # …,
        'DIRS': TEMPLATE_DIRS,
        # …
    }
  ]