This prints empty list!

eightqueens.py

queens = []

def legalize(past):
    row = [0 for i in range(8)]
    for p_row in range(len(past)):
        for i in range(len(past[p_row])):
            if past[p_row][i] == "Q":
                row[i] = 1
                if i - p_row >= 0:
                    row[i - p_row] = 1
                if i + p_row <= 7:
                    row[i + p_row] = 1
    return row


def eight_queens(past=[]):
    #print(past)
    if not past:
        past += [[1 for i in range(8)]]
        print(past)
        for i in range(8):
            past[0][i] = "Q"
            eight_queens(past)
            past[0][i] = 1
    else:
        if len(past) == 8:
            queens.append(past)
        else:
            #print(past)
            new_row = legalize(past)
            #print(new_row)
            for n_row in range(len(new_row)):
                if new_row[n_row] == 0:
                    new_row[n_row] = "Q"
                    eight_queens(past + [new_row])
                    new_row[n_row] = 0
        
        
eight_queens()
print(queens)