from matplotlib import pyplot as plt
class1 = [(3, 4), (4.2, 5.3), (4, 3), (6, 5), (4, 6), (3.7, 5.8),
(3.2, 4.6), (5.2, 5.9), (5, 4), (7, 4), (3, 7), (4.3, 4.3) ]
class2 = [(-3, -4), (-2, -3.5), (-1, -6), (-3, -4.3), (-4, -5.6),
(-3.2, -4.8), (-2.3, -4.3), (-2.7, -2.6), (-1.5, -3.6),
(-3.6, -5.6), (-4.5, -4.6), (-3.7, -5.8) ]
X, Y = zip(*class1)
plt.scatter(X, Y, c="r")
X, Y = zip(*class2)
plt.scatter(X, Y, c="b")
plt.show()