code: def get_user_permission_full_codename(perm):
      
      User = get_user_model()
      return '%s.%s_%s' % (User._meta.app_label, perm, User._meta.module_name)
docs: Returns 'app_label.<perm>_<usermodulename>'. If standard ``auth.User`` is
      used, for 'change' perm this would return ``auth.change_user`` and if
      ``myapp.CustomUser`` is used it would return ``myapp.change_customuser``.