docs: def _get_all_migrations():
      """ Returns sorted list of all migrations.
  
      Returns:
          list of (int, str) tuples: first elem of the tuple is migration number, second if module name.
  
      """
      from . import migrations
  
      package = migrations
      prefix = package.__name__ + '.'
      all_migrations = []
      for importer, modname, ispkg in pkgutil.iter_modules(package.__path__, prefix):
          version = int(modname.split('.')[-1].split('_')[0])
          all_migrations.append((version, modname))
  
      all_migrations = sorted(all_migrations, key=lambda x: x[0])
      return all_migrations