@classmethod
def from_queryset(cls, other, **kwargs):
    """根据其他QuerySet对象的数据生成实例"""
    query = other.query.clone()
    if other._sticky_filter:
        query.filter_is_sticky = True
    clone = cls(model=other.model, query=query, using=other._db, hints=
        other._hints)
    clone._for_write = other._for_write
    clone._prefetch_related_lookups = other._prefetch_related_lookups[:]
    clone._known_related_objects = other._known_related_objects
    clone._iterable_class = other._iterable_class
    clone._fields = other._fields
    clone.__dict__.update(kwargs)
    return clone
