Python Encapsulation Question

1 points · submitted Oct 2019 by u/EndUsersarePITA

Hi there, I've got some experience with writing Java and have decided to attempt to pick up Python via Automatetheboringstuff (which is pretty good I must say).

So in chapter 8 (reading and writing files) there is an exercise to generate a bunch quizzes with randomized order of answers. I'm trying to write my own implementation before comparing it to the given answers. However I've stumbled upon a concept in python that has confused me.

My code is at https://pastebin.com/6sEMMKeT

For some reason, when I iterate through the list of states and remove the correct answer, it seems to remove the capital for the global variable as well. I assumed that when I linked the global variable to a local variable in a for loop, the global should not be affected. But here, I'm seeing a decrease even in the global variable.

Is this normal behaviour or have I missed a major concept in programming?

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novice_at_life 1 points · Oct 2019

When you say wrongAns = capList you're just making a new pointer to the same list. Instead you want to import copy and say wrongAns = Copy.copy(capList) this will give you a copy of the list that you can change without affecting the original.

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EndUsersarePITA [OP] 1 points · Oct 2019

OOOOHHHH.... its a pointer assignation? I did not know that. I thought it would create a new object. How come this does not apply to variables as well? For example :

x = 1
y = x
print(str(y)) #results 1
x = 2
print(str(y)) #results 1

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