list[]:        可变，append/1,insert/2,pop/index?

 tuple():    不变

 dict{}:        可变,values/0,itervalues/0,values/0,iteritems/0,items/0

 set([]):    可变，add/1,remove/index

 str:  .join/list  .capitalize/0 .title/0 .upper/0  .lower/0 .strip(rm),

 len/1,

 enumerate/1,

 zip/2,

 isinstance/(var,type),

 map/(fun/1,list),

 reduce/((fun/2+start?),list),

 filter/(fun/1,list),

 sorted/(list,diy_cmp_fun/2),

 !def!内层函数引用了外层函数的参数，然后返回内层函数的情况，称为闭包(Closure)

 !ex!

 def calc_sum(lst):

     def lazy_sum():

         return sum(lst)

     return lazy_sum

 !note!不要引用任何循环变量，或者后续会发生变化的变量

 !dying!

 def count():

     fs = []

     L=range(1,4)

     for i in range(1, 4):

         def f(j):

             def g():

                 return j*j

             return g

         r=f(i)

         fs.append(r)

     return fs

 f1, f2, f3 = count()

 print f1(), f2(), f3()