2018-08-19

一、==和is的区别：

*==

比较两个对象是否相等

a = [11，22，33]
b = a
a == b
True
a = 23
b = a 
a == b
True

a = [11,22,33]
b = [11,22,33]
a == b
True
a = 24
b = 24
a == b
True

*is

比较两个引用是否指向了同一个对象（引用比较）(大于256就是false)

a = 180
b = 180
a is b
True
a = 257
b = 257
a is b
False

a = 257
b = a
a is b
True
a = 180
b = a
a is b
True

a = [11,22]
b = [11,22]
a is b
False
a = [11,22]
b = a
a is b
True

二、深拷贝、浅拷贝

*浅拷贝：（拷贝了引用，并没有拷贝内容）

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*深拷贝：（对于一个对象所有层次的拷贝）

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