def exclude_current_instance(self, queryset):
        """
        If an instance is being updated, then do not include
        that instance itself as a uniqueness conflict.
        """
        if self.instance is not None:
            return queryset.exclude(pk=self.instance.pk)
        return queryset
def exclude_current_instance ( self , queryset ) : if self . instance is not None : return queryset . exclude ( pk = self . instance . pk ) return queryset
If an instance is being updated, then do not include
        that instance itself as a uniqueness conflict.