"""
变量: id: 在内存中存储的位置;id(a) value: == type:变量的数据类型; type(a) ==: value, type is: 三个都判断
==：只判断value和type，不判断id
** a is b ====> True, a==b一定相等， 返回True; ** a==b ====> True, a is b 不一定;
PyDev console: starting. import sys; print('Python %s on %s' % (sys.version, sys.platform)) sys.path.extend(['/root/PycharmProjects/day04']) Python 3.6.4 (default, Aug 7 2018, 11:03:35) [GCC 4.8.2 20140120 (Red Hat 4.8.2-16)] on linux a = '1' b = 1 a == b False a = '1' b = a a is b True li = [1,2,3] li1 = li li == li1 True li is li1 True li2 = li.copy() id(li)
"""
变量: id: 在内存中存储的位置;id(a) value: == type:变量的数据类型; type(a) ==: value, type is: 三个都判断
** a is b ====> True, a==b一定相等， 返回True; ** a==b ====> True, a is b 不一定;
PyDev console: starting. import sys; print('Python %s on %s' % (sys.version, sys.platform)) sys.path.extend(['/root/PycharmProjects/day04']) Python 3.6.4 (default, Aug 7 2018, 11:03:35) [GCC 4.8.2 20140120 (Red Hat 4.8.2-16)] on linux a = '1' b = 1 a == b False a = '1' b = a a is b True li = [1,2,3] li1 = li li == li1 True li is li1 True li2 = li.copy() id(li) 140479313773128 id(li2) 140479313773704 ##注意此时li2和li的type和value是一样的，但id不同 li [1, 2, 3] li2 [1, 2, 3] li == li2 True li is li2 False
"""
变量: id: 在内存中存储的位置;id(a) value: == type:变量的数据类型; type(a) ==: value, type is: 三个都判断
** a is b ====> True, a==b一定相等， 返回True; ** a==b ====> True, a is b 不一定;
PyDev console: starting. import sys; print('Python %s on %s' % (sys.version, sys.platform)) sys.path.extend(['/root/PycharmProjects/day04']) Python 3.6.4 (default, Aug 7 2018, 11:03:35) [GCC 4.8.2 20140120 (Red Hat 4.8.2-16)] on linux a = '1' b = 1 a == b False a = '1' b = a a is b True li = [1,2,3] li1 = li li == li1 True li is li1 True li2 = li.copy() id(li) 140198653811208 id(li2) 140198653810120 li [1, 2, 3] li2 [1, 2, 3] li == li2 True li is li2 False
"""
