def _componentSortKey(componentAndType):
        """Sort SET components by tag

        Sort depending on the actual Choice value (dynamic sort)
        """
        component, asn1Spec = componentAndType

        if asn1Spec is None:
            compType = component
        else:
            compType = asn1Spec

        if compType.typeId == univ.Choice.typeId and not compType.tagSet:
            if asn1Spec is None:
                return component.getComponent().tagSet
            else:
                # TODO: move out of sorting key function
                names = [namedType.name for namedType in asn1Spec.componentType.namedTypes
                         if namedType.name in component]
                if len(names) != 1:
                    raise error.PyAsn1Error(
                        '%s components for Choice at %r' % (len(names) and 'Multiple ' or 'None ', component))

                # TODO: support nested CHOICE ordering
                return asn1Spec[names[0]].tagSet

        else:
            return compType.tagSet
Sort SET components by tag

        Sort depending on the actual Choice value (dynamic sort)
        
stackoverflow/venv/lib/python3.6/site-packages/pyasn1/codec/der/encoder.py