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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def workflow_states_column(self, obj):
 """ Return text description of workflow states assigned to object """

        workflow_states = models.WorkflowState.objects.filter(
            content_type=self._get_obj_ct(obj),
            object_id=obj.pk,
        )
        return ', '.join([unicode(wfs) for wfs in workflow_states])