Fixed a bug backticks

fix

    you may optionally exclude the ``self.check_object_permissions, and simply return the object from the `get_object_or_404` lookup.

to

    you may optionally exclude the `self.check_object_permissions`, and simply return the object from the `get_object_or_404` lookup.
Merge pull request #1387 from RicterZ/patch-1

Fixed a bug backticks