Are the outputs same? Are the outputs different? Why?

Q. Predict the output of following two parts. Are the outputs same? Are the outputs different? Why?

(a)

L1, L2 = [2, 4], [2, 4]

L3 = L2

L2[1] = 5

print(L3)

(b)

L1, L2 = [2, 4], [2, 4]

L3 = list(L2)

L2[1] = 5

print (L3)

Answer =

Output:

(a)

[2, 5]

(b)

[2, 4]

Because (a) is true copy which mean L1 & L2 are like aliases for the same list. So for if we change list then L1 & L2 value also change.

While in (b) L3 is true independent copy of a list L2. So for after executing program if we change list of L2 then list of L3 will not change.