python3.0 字典key排序

IDLE 3.0
>>> dic = {"aa":1,"bb":2,"ab":3}
>>> dic
{'aa': 1,'ab': 3,'bb': 2}
>>> for k in sorted(dic.keys()):
print (k)

aa
ab


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字典对象其实就是键-值对
下面是字典对象的添加，修改，删除
(修改与添加方法相同，当key值不存在的时候添加)
>>> dic["cc"] = 4
>>> dic
{'aa': 1,'cc': 4,'bb': 2}
>>> dic["bc"] = 5
>>> dic
{'aa': 1,'bb': 2,'bc': 5}
>>> dic["cc"] = 6
>>> dic
{'aa': 1,'cc': 6,'bc': 5}
>>> del dic["cc"]
>>> dic
{'aa': 1,'bc': 5}