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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 order_queryset(self, queryset):
 """ Orders the passed in queryset, returning a new queryset in response. By default uses the _order query parameter. """

        order = self.derive_ordering()

        # if we get our order from the request
        # make sure it is a valid field in the list
        if '_order' in self.request.GET:
            if order.lstrip('-') not in self.derive_fields():
                order = None

        if order:
            # if our order is a single string, convert to a simple list
            if isinstance(order, str):
                order = (order,)

            queryset = queryset.order_by(*order)

        return queryset