import pandas as pd
%matplotlib inline
import matplotlib.pyplot as plt

df = pd.DataFrame({
    'X1':[1,2,2,4,5,6,7,8,8,10],
    'X2':[10,11,9,12,13,20,22,23,25,27],
    'Y':[1,1,1,1,1,2,2,2,2,2]
})

X = df.iloc[:, :2].values
Y = df.iloc[:, 2].values

plt.scatter(X[:5, 0], X[:5, 1], color='red', marker='o', label='Y = 1')
plt.scatter(X[5:10, 0], X[5:10, 1], color='blue', marker='o', label='Y = 2')

plt.xlabel('X1')
plt.ylabel('X2')
plt.legend(loc='upper left')

plt.show()