（1）cmd.get():打印出设置的当前值
（2）cmd.set(name,value,selection,state): 进行改变
cmd.set(string name, string value, string selection, int state,
int updates, int quiet)
value:{default=1}
selection: name-pattern or selection-expression {default:'' (global)}
state:a state number {default: 0 (per-object setting)}
example:
set surface_color, white, 1hpv
（3）set dot_solvent, on ：溶剂可及表面积
(4)cmd.create() ：创造新的对象
(5)cmd.disable() : 关闭对象
(6)cmd.get_area()：依靠dot_solvent 的setting,获取选区的表面积。
get_area [ selection [, state [, load_b ]]]
load_b = bool: store per-atom surface area in b-factors {default: 0}
(将各原子的溶剂可及表面积 放入b-factors)
(7) alter spike, b=b-q 如果是接触面氨基酸，此值大于0
