python里面声明多个变量 a = b = c = 1 这样有问题吗

Question

python里面声明多个变量 a = b = c = 1 这样有问题吗
以前在 javascript 里面这样声明 var a = b = c = 1 ，b 和 c 会变成全局变量。
不知道 python 里面这样声明安全吗？

Answer 1

Safe, but for reference types such as lists, dictionaries, and classes, a, b, and c will all point to the same reference, instead of creating three independent variables

Answer 2

Safe

When python loads other files, it needs to be explicitly imported before it can import the variables of other files (as long as you are not from XXX import *), so there is no need to worry about the variables of the two files contaminating each other

Answer 3

A problem arises when using a = b = c = []. The same address is referenced. Modifying the value of a will affect b and c

Answer 4

That’s okay

if 1 < number < 10:
    print number
    
while 1 < num < 10: 

Answer 5

No problem, this is a syntax unique to Python, equivalent to

a=1
b=1
c=1

And in js it will become

c=1;
b=c;
var a = b;

Answer 6

Just distinguish between mutable types and immutable types