title: Django No module named 'django.db.migrations.migration'
body: <p>I had a custom user model in my project. I wanted to delete it and return default user model by deleting <strong>all</strong> tables in my database and deleting migrations. After this, I tried to run <code>python manage.py makemigrations</code> command but it writes:</p>
  
  <pre><code>Traceback (most recent call last):
    File "manage.py", line 15, in &lt;module&gt;
      execute_from_command_line(sys.argv)
    File "/home/irakliy01/Projects/Project/PythonVEnv/lib/python3.6/site-packages/django/core/management/__init__.py", line 371, in execute_from_command_line
      utility.execute()
    File "/home/irakliy01/Projects/Project/PythonVEnv/lib/python3.6/site-packages/django/core/management/__init__.py", line 347, in execute
      django.setup()
    File "/home/irakliy01/Projects/Project/PythonVEnv/lib/python3.6/site-packages/django/__init__.py", line 24, in setup
      apps.populate(settings.INSTALLED_APPS)
    File "/home/irakliy01/Projects/Project/PythonVEnv/lib/python3.6/site-packages/django/apps/registry.py", line 89, in populate
      app_config = AppConfig.create(entry)
    File "/home/irakliy01/Projects/Project/PythonVEnv/lib/python3.6/site-packages/django/apps/config.py", line 116, in create
      mod = import_module(mod_path)
    File "/usr/lib/python3.6/importlib/__init__.py", line 126, in import_module
      return _bootstrap._gcd_import(name[level:], package, level)
    File "&lt;frozen importlib._bootstrap&gt;", line 994, in _gcd_import
    File "&lt;frozen importlib._bootstrap&gt;", line 971, in _find_and_load
    File "&lt;frozen importlib._bootstrap&gt;", line 955, in _find_and_load_unlocked
    File "&lt;frozen importlib._bootstrap&gt;", line 665, in _load_unlocked
    File "&lt;frozen importlib._bootstrap_external&gt;", line 678, in exec_module
    File "&lt;frozen importlib._bootstrap&gt;", line 219, in _call_with_frames_removed
    File "/home/irakliy01/Projects/Project/PythonVEnv/lib/python3.6/site-packages/django/contrib/contenttypes/apps.py", line 9, in &lt;module&gt;
      from .management import (
    File "/home/irakliy01/Projects/Project/PythonVEnv/lib/python3.6/site-packages/django/contrib/contenttypes/management/__init__.py", line 2, in &lt;module&gt;
      from django.db import DEFAULT_DB_ALIAS, migrations, router, transaction
    File "/home/irakliy01/Projects/Project/PythonVEnv/lib/python3.6/site-packages/django/db/migrations/__init__.py", line 1, in &lt;module&gt;
      from .migration import Migration, swappable_dependency  # NOQA
  ModuleNotFoundError: No module named 'django.db.migrations.migration'
  </code></pre>
  
  <p>I have no idea what I did wrong.</p>