I need to random solution for 8 queen puzzle. But I can just produce 1 solution and it is always same. Can someone help me please?

import numpy as np

board = np.zeros( (8,8), int)

Get the diagonal 'index' for any point (m,n)

def getdiagd(m,n):

if (m == n):
    return 0
else:
    return (n-m)

def getCollisionCount(m,n,b):

# Get row and col sums for row m, col n

colsum = np.sum(b, axis=0)[n]
rowsum = np.sum(b, axis=1)[m]

# Get sum of diagonal that includes (m,n)
d = getdiagd(m,n)
ddiagsum = np.sum(b.diagonal(d))

# Rotate board 270 degrees CCW (90 CW) and get diagonal that includes (n, 7-m)
# This is the same as finding the sum of the upward diagonal of the original board
# just a lot easier.
udiagsum = np.sum(np.rot90(b, 3).diagonal(d))
return (colsum + rowsum + ddiagsum + udiagsum)

def queens(m):

if m > 7:
    print (board)
    return True
for n in range(8):

    if getCollisionCount(m,n, board) == 0:
        board[m][n] = 1
        if queens(m+1):
            return True
        else:
            board[m][n] = 0
return False

queens(0)