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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_list_filter(self, request):
 """ Adds versionable custom filtering ability to changelist """

        list_filter = super(VersionedAdmin, self).get_list_filter(request)
        return list(list_filter) + [('version_start_date', DateTimeFilter),
                                    IsCurrentFilter]