Python shares references to multiple variables to reference sample code

a = 3
b = a

Let's start with the figure above (figure 1). It's easy to see:

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The variable name and the object, after the assignment statement b = a is run, the variables a and b both point to the memory space of object 3.
Assuming that a = 'python' is executed, a will point to the string object just created.
Let's try this again:

>>>list_1 = [1,2,3,4]
>>>list_2 = list_1
>>>list_2
>>>list_1[0] = 'python'
>>>list_2

The result:

[1,2,3,4]
['python',2,3,4]

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From my understanding, it is explained that list is a type object, and each element in the object can be regarded as a variable. To reference the object list_1 = [1,2,3,4] with different memory space is to make list_1 point to the memory space of the list. When list_2 = list_1, they will point to the same memory space. When List_1[0] changes the direction, list_2 still points to the list object, so it is seen that the value of List_1[0] is changed. In fact, python directly goes to the memory space to modify the direction of list_2 without any variable.
Maybe that's not what we want. If you don't want this to happen, you need to copy python objects instead of creating references.
Such as:

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