old_contents: from django.conf import settings
  from django.utils.translation import ugettext as _
  
  from .exceptions import AppAlreadyInstalledException
  from .utils import resolve_appinstance
  
  PERMISSION_MSG_DELETE = _("You are not permitted to delete this Instance")
  PERMISSION_MSG_GENERIC = _("You do not have permissions for this Instance.")
  PERMISSION_MSG_MODIFY = _("You are not permitted to modify this Instance")
  PERMISSION_MSG_METADATA = _(
      "You are not permitted to modify this Instance's metadata")
  PERMISSION_MSG_VIEW = _("You are not permitted to view this Instance")
  
  
  def can_change_app_instance(function):
      def wrap(request, *args, **kwargs):
          instance_id = kwargs.get('instance_id', None)
          assert instance_id
          resolve_appinstance(request, instance_id, 'base.change_resourcebase',
                              PERMISSION_MSG_MODIFY)
          return function(request, *args, **kwargs)
  
      wrap.__doc__ = function.__doc__
      wrap.__name__ = function.__name__
      return wrap
  
  
  def can_view_app_instance(function):
      def wrap(request, *args, **kwargs):
          instance_id = kwargs.get('instance_id', None)
          assert instance_id
          resolve_appinstance(request, instance_id, 'base.view_resourcebase',
                              PERMISSION_MSG_VIEW)
          return function(request, *args, **kwargs)
  
      wrap.__doc__ = function.__doc__
      wrap.__name__ = function.__name__
      return wrap
  
  
  def restart_enabled(func):
      def wrap(*args, **kwargs):
          if not getattr(settings, "CARTOVIEW_TEST", False):
              return func(*args, **kwargs)
          else:
              pass
  
      return wrap
  
  
  def rollback_on_failure(func):
      def wrap(*args, **kwargs):
          this = args[0]
          try:
              return func(*args, **kwargs)
          except BaseException as e:
              if not isinstance(e, AppAlreadyInstalledException):
                  if hasattr(this, '_rollback'):
                      this._rollback()
                      raise e
  
      return wrap
  
new_contents: from django.conf import settings
  from django.utils.translation import ugettext as _
  
  from .exceptions import AppAlreadyInstalledException
  from .utils import resolve_appinstance
  
  PERMISSION_MSG_DELETE = _("You are not permitted to delete this Instance")
  PERMISSION_MSG_GENERIC = _("You do not have permissions for this Instance.")
  PERMISSION_MSG_MODIFY = _("You are not permitted to modify this Instance")
  PERMISSION_MSG_METADATA = _(
      "You are not permitted to modify this Instance's metadata")
  PERMISSION_MSG_VIEW = _("You are not permitted to view this Instance")
  
  
  def can_change_app_instance(function):
      def wrap(request, *args, **kwargs):
          instance_id = kwargs.get('instance_id', None)
          assert instance_id
          resolve_appinstance(request, instance_id, 'base.change_resourcebase',
                              PERMISSION_MSG_MODIFY)
          return function(request, *args, **kwargs)
  
      wrap.__doc__ = function.__doc__
      wrap.__name__ = function.__name__
      return wrap
  
  
  def can_view_app_instance(function):
      def wrap(request, *args, **kwargs):
          instance_id = kwargs.get('instance_id', None)
          assert instance_id
          resolve_appinstance(request, instance_id, 'base.view_resourcebase',
                              PERMISSION_MSG_VIEW)
          return function(request, *args, **kwargs)
  
      wrap.__doc__ = function.__doc__
      wrap.__name__ = function.__name__
      return wrap
  
  
  def restart_enabled(func):
      def wrap(*args, **kwargs):
          if not getattr(settings, "CARTOVIEW_TEST", False):
              return func(*args, **kwargs)
      return wrap
  
  
  def rollback_on_failure(func):
      def wrap(*args, **kwargs):
          this = args[0]
          try:
              return func(*args, **kwargs)
          except BaseException as e:
              if not isinstance(e, AppAlreadyInstalledException):
                  if hasattr(this, '_rollback'):
                      this._rollback()
                      raise e
  
      return wrap
  
subject: remove redundant else block