[1.9.x] Fixed #25627, refs #25618 -- Removed detection of south migrations in loader.

                    if import_name[0] not in "_.~":

                        migration_names.add(import_name)

            # Load them

            south_style_migrations = False

            for migration_name in migration_names:

                try:

                migration_module = import_module("%s.%s" % (module_name, migration_name))

                except ImportError as e:

                    # Ignore South import errors, as we're triggering them

                    if "south" in str(e).lower():

                        south_style_migrations = True

                        break

                    raise

                if not hasattr(migration_module, "Migration"):

                    raise BadMigrationError(

                        "Migration %s in app %s has no Migration class" % (migration_name, app_config.label)

                    )

                # Ignore South-style migrations

                if hasattr(migration_module.Migration, "forwards"):

                    south_style_migrations = True

                    break

                self.disk_migrations[app_config.label, migration_name] = migration_module.Migration(

                    migration_name,

                    app_config.label,

                )

            if south_style_migrations:

                if app_config.label in self.migrated_apps:

                    raise BadMigrationError(

                        "Migrated app %r contains South migrations. Make sure "

                        "all numbered South migrations are deleted prior to "

                        "creating Django migrations." % app_config.label

                    )

                self.unmigrated_apps.add(app_config.label)

    def get_migration(self, app_label, name_prefix):

        "Gets the migration exactly named, or raises `graph.NodeNotFoundError`"