Thank you. I have followed the instruction( https://wiki.list.org/DOC/Mailman%203%20installation%20experience). urls.py, production.py and settings_local.py have been changed. I got an ImportError.
Traceback (most recent call last):
File "/usr/lib/python2.7/wsgiref/handlers.py", line 85, in run
self.result = application(self.environ, self.start_response)File "/opt/mailman/mailman-bundler/eggs/Django-1.8.15-py2.7.egg/django/contrib/staticfiles/handlers.py", line 63, in __call__
return self.application(environ, start_response)File "/opt/mailman/mailman-bundler/eggs/Django-1.8.15-py2.7.egg/django/core/handlers/wsgi.py", line 170, in __call__
self.load_middleware()File "/opt/mailman/mailman-bundler/eggs/Django-1.8.15-py2.7.egg/django/core/handlers/base.py", line 50, in load_middleware
mw_class = import_string(middleware_path)File "/opt/mailman/mailman-bundler/eggs/Django-1.8.15-py2.7.egg/django/utils/module_loading.py", line 26, in import_string
module = import_module(module_path)File "/usr/lib/python2.7/importlib/__init__.py", line 37, in import_module
__import__(name)ImportError: No module named middleware