Remove nasty error message checking hack

django/core/management/commands/migrate.py

@@ -12,6 +12,7 @@ from django.db.migrations.executor import MigrationExecutor
 from django.db.migrations.loader import AmbiguityError
 from django.utils.datastructures import SortedDict
 from django.utils.importlib import import_module
+from django.utils.module_loading import module_has_submodule, import_by_path
 
 
 class Command(BaseCommand):
@@ -40,21 +41,8 @@ class Command(BaseCommand):
         # Import the 'management' module within each installed app, to register
         # dispatcher events.
         for app_name in settings.INSTALLED_APPS:
-            try:
+            if module_has_submodule(import_module(app_name), "management"):
                 import_module('.management', app_name)
-            except ImportError as exc:
-                # This is slightly hackish. We want to ignore ImportErrors
-                # if the "management" module itself is missing -- but we don't
-                # want to ignore the exception if the management module exists
-                # but raises an ImportError for some reason. The only way we
-                # can do this is to check the text of the exception. Note that
-                # we're a bit broad in how we check the text, because different
-                # Python implementations may not use the same text.
-                # CPython uses the text "No module named management"
-                # PyPy uses "No module named myproject.myapp.management"
-                msg = exc.args[0]
-                if not msg.startswith('No module named') or 'management' not in msg:
-                    raise
 
         # Get the database we're operating from
         db = options.get('database')