Explanation:
Line 1: Create a List
a = [1, 2]
Explanation:
A list named a is created.
It contains two elements: 1 and 2.
Memory:
a ──► [1, 2]
Line 2: Copy the List
b = a.copy()
Explanation:
copy() creates a new list with the same elements as a.
Now a and b are different lists stored in different memory locations.
Memory:
a ──► [1, 2]
b ──► [1, 2]
Important: Changes made to b will not affect a.
Line 3: Add an Element
b.append(3)
Explanation:
append(3) adds the value 3 to the end of list b.
Now:
a ──► [1, 2]
b ──► [1, 2, 3]
Only b changes because it is a separate copy.
Line 4: Print the Original List
print(a)
Explanation:
This prints the original list a.
Since a was never modified, it still contains only 1 and 2.
Output:
[1, 2]
Final Memory Diagram
Before append():
a ──► [1, 2]
b ──► [1, 2]
After append():
a ──► [1, 2]
b ──► [1, 2, 3]
Why doesn't a change?
Because:
a.copy() creates a new independent list.
b.append(3) modifies only the new list b.
The original list a remains unchanged.
Final Output
[1, 2]
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