import matplotlib.pyplot as plt
X, Y = zip(*in_time)
X2, Y2 = zip(*too_late)
bar_width = 0.9
plt.bar(X, Y, bar_width,
color="blue", alpha=0.75, label="in time")
bar_width = 0.8
plt.bar(X2, Y2, bar_width,
color="red", alpha=0.75, label="too late")
plt.legend(loc='upper right')
plt.show()