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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 _get_obj_ct(self, obj):
 """ Look up and return object's content type and cache for reuse """

        if not hasattr(obj, '_wfct'):
            # Use polymorpic content type if available
            if hasattr(obj, 'polymorphic_ctype'):
                obj._wfct = obj.polymorphic_ctype
            else:
                obj._wfct = ContentType.objects.get_for_model(obj)
        return obj._wfct