Is it possible to have an explanation of this code plz ?

Question

A = [1,2,3,4,1]
for n in A:
A[n] = 0
print (A)

Why does it output [0,0,3,0,1] ?

Answer 1

starting A = [1,2,3,4,1]
for loop goes through each value of A:
#n = A[0]
A[1] = 0 # A=[1,0,3,4,1]
#n = A[1]
A[0]= 0 # A=[0,0,3,4,1]
#n = A[2]
A[3]= 0 # A=[0,0,3,0,1]
#n = A[3]
A[0] = 0 # A=[0,0,3,0,1]
#n = A[4]
A[1]= 0 # A=[0,0,3,0,1]
loop terminates