Function does not modify the Matrix after the second call!

Question

I’m making a small game, however, I need to call this function 3 times, in the first call of the function it performs as expected, however, in the second and third call it does not do what I expect. That is, from the second call it does not modify the matrix ( it takes the original matrix and not the modified matrix after the first call ) which is what I need because that’s why I created the function. function does not modify the matrix outside the function? I can not put the matrix inside the function, pq it would be executed 3 times.

import random
import time
Tamanho = 21
Matriz = [[0]* 7 for i in range(3)]
Lista_De_Numeros = [Numero + 1 for Numero in range(Tamanho)]
for i in range(3):
    for j in range(7):
        Numero = random.choice(Lista_De_Numeros)
        Matriz[i][j] = Numero
        Lista_De_Numeros.remove(Numero)
def Escolha (M):
    Linha_Do_Numero = int(input("Qual a linha que seu número ficou ? "))
    if Linha_Do_Numero == 1:
        M = [(M[1]), (M[0]), (M[2])]
        print(M)
        M = [[(M[0][6]), (M[0][3]), (M[0][0]), (M[1][4]), (M[1][1]), (M[2][5]),(M[2][2]) ], [(M[0][5]), (M[0][2]), (M[1][6]), (M[1][3]), (M[1][0]), (M[2][4]), (M[2][1])], [(M[0][4]), (M[0][1]), (M[1][5]), (M[1][2]), (M[2][6]), (M[2][3]), (M[2][0])]]
        print(M)
    elif Linha_Do_Numero == 2:
        M= [(M[0]), (M[1]), (M[2])]
        print (M)
        M = [[(M[2][6]), (M[2][3]), (M[2][0]), (M[1][4]), (M[1][1]), (M[0][5]),(M[0][2]) ], [(M[2][5]), (M[2][2]), (M[1][6]), (M[1][3]), (M[1][0]), (M[0][4]), (M[0][1])], [(M[2][4]), (M[2][1]), (M[1][5]), (M[1][2]), (M[0][6]), (M[0][3]), (M[0][0])]]
        print (M)
    elif Linha_Do_Numero == 3:
        M= [(M[0]), (M[2]), (M[1])]
        print (M)
        M = [[(M[2][6]), (M[2][3]), (M[2][0]), (M[1][4]), (M[1][1]), (M[0][5]),(M[0][2]) ], [(M[2][5]), (M[2][2]), (M[1][6]), (M[1][3]), (M[1][0]), (M[0][4]), (M[0][1])], [(M[2][4]), (M[2][1]), (M[1][5]), (M[1][2]), (M[0][6]), (M[0][3]), (M[0][0])]]                   
        print (M)
print()
print("                              Escolha um único número abaixo")
print()
print('       linha 1','                        linha 2','                      linha 3')
print()
print (Matriz[0],'     ',Matriz[1],'     ',Matriz[2])
print()
Escolha(Matriz)
print()
Escolha(Matriz)
print()
Escolha(Matriz)
print()
print(Matriz[1][3])

Answer 1

Python arrays are passed by reference, that is, the modifications made in a function are passed back to the matrix definition we made outside the scope of the function. An example:

matriz = [[0]*3 for i in range(3)]

print("matriz original " , matriz)

def escolha(m):
    for i in range(3):
        for j in range(3):
            'alguma operacao na matriz'
            m[i][j] = m[i][j] + 1
    return m

escolha(matriz)

print("funcao um modifica a matriz original", matriz)

escolha(matriz)

print("funcao dois também modifica a matriz original", matriz)

What returns:

matriz original  [[0, 0, 0], [0, 0, 0], [0, 0, 0]]                                                                                            
funcao um modifica a matriz original [[1, 1, 1], [1, 1, 1], [1, 1, 1]]                                                                        
funcao dois também modifica a matriz original [[2, 2, 2], [2, 2, 2], [2, 2, 2]]