'Reverses the ordering of the QuerySet.'

def reverse(self):

    clone = self._clone()
    assert self._ordering, 'You    need    to    set    an    ordering    for    reverse'
    ordering = []
    for order in self._ordering:
        for (k, v) in order.items():
            if (v == 'asc'):
                ordering.append({k: 'desc'})
            else:
                ordering.append({k: 'asc'})
    clone._ordering = ordering
    return clone
