python中的id()

id(object)Return the “identity” of an object. This is an integer (or long integer) which is guaranteed to be unique and constant for this object during its lifetime. Two objects with non-overlapping lifetimes may have the same id() value.CPython implementation detail: This is the address of the object in memory.说起这个函数就需要先了解pyhton的变量存储机制了：变量：是动态变量，不用提前声明类型。当我们写：a = ‘ABC’时，Python解释器干了两件事情：在内存中创建了一个’ABC’的字符串；在内存中创建了一个名为a的变量，并把它指向’ABC’。id(a)读取的是a的内存地址