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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_fields(self, request, obj=None):
 """ For subclasses of ``Orderable``, the ``_order`` field must always be present and be the last field. """

        fields = super(BaseDynamicInlineAdmin, self).get_fields(request, obj)
        if issubclass(self.model, Orderable):
            fields = list(fields)
            try:
                fields.remove("_order")
            except ValueError:
                pass
            fields.append("_order")
        return fields