def main():
    nrows = 2
    fig, axes = plt.subplots(nrows, 2)

    for row in axes:
        x = [1,2,3,4]
        y = [1,2,3,4]
        plot(row, x, y)

    plt.show()

def plot(axrow, x, y):
    axrow[0].plot(x, color='red')
    axrow[1].plot(y, color='green')