t.py

def checkRows(g):
    for rows in g:
        numbersInRow = [] #List to keep track of numbers that appear in the row
        for number in row:
            if number != 0 and number in numbersInRow:
                return g.index(row) #The number has already appeared in the row, so return the row that fails
            else:
                numbersInRow.append(number) #This number hasnt appeared in the row yet, so add it to the list
        print(numbersInRow)
    return True #Nothing failed, so the row check succeeded