i was trying to verify if a number from a list already exist in a column matrix, but still repeating. Someone can help me? 

```
import random
    numbers = [1,2,3,4,5,6,7,8,9]
    matrix = [[None for i in range(9)] for j in range(9)]

def createMatrix():
    for i in range(9):
        for j in range(9):
            cop = numbers[:]
            random.shuffle(cop)
            while matrix[i][j] is None:
                temp = veriCol(matrix, j, cop)
                if temp == 0:
                    matriz[i] = cop
                else: 
                    return None

def veriCol(matrix, col, value):
    tmp = 0
    for l in range(9):
        #print("Vc {}".format(l)),
        if value == matrix[l][col]:
            tmp = 1

    return tmp

createMatrix()
for i in range(9):
    print(matriz[i])

```