          Because of the way class based views create a closure around the
          instantiated view, we need to totally reimplement `.as_view`,
          and slightly modify the view function that is created and returned.
          """
          # The suffix initkwarg is reserved for identifing the viewset type
          # eg. 'List' or 'Instance'.
          cls.suffix = None
  
          # actions must not be empty
          if not actions:
 
</s> remove     don't need to dig into the implemention.
 </s> add     don't need to dig into the implementation. </s> remove             # a 404 reponse.
 </s> add             # a 404 response. </s> remove             # Get the model field that is refered too.
 </s> add             # Get the model field that is referred too. </s> remove         # types might return a non-primative value for the pk otherwise.
 </s> add         # types might return a non-primitive value for the pk otherwise. </s> remove         # `fields` is evalutated lazily. We do this to ensure that we don't
 </s> add         # `fields` is evaluated lazily. We do this to ensure that we don't
        # The suffix initkwarg is reserved for identifying the viewset type
          Because of the way class based views create a closure around the
          instantiated view, we need to totally reimplement `.as_view`,
          and slightly modify the view function that is created and returned.
          """
        # The suffix initkwarg is reserved for identifying the viewset type
          # eg. 'List' or 'Instance'.
          cls.suffix = None
  
          # actions must not be empty
          if not actions:
keep keep keep keep replace keep keep keep keep keep
 Removed unused imports, pep8 fixes, typo fixes 
rest_framework/viewsets.py