python之函数用法fromkeys()

# -*- coding: utf-8 -*-#python 27#xiaodeng#python之函数用法fromkeys()#fromkeys()#说明：用于创建一个新字典，以序列seq中元素做字典的键，value为字典所有键对应的初始值'''>>> help(dict.fromkeys)Help on built-in function fromkeys:fromkeys(...)    dict.fromkeys(S[,v]) -> New dict with keys from S and values equal to v.    v defaults to None.'''#案例d=[1,2,3]dict={}dict=dict.fromkeys(d)print dict                          #{1: None, 2: None, 3: None}dict=dict.fromkeys(d,'xiaodeng')    #xiaodeng为默认值print dict                          #{1: 'xiaodeng', 2: 'xiaodeng', 3: 'xiaodeng'}