Expected:

Output:
import matplotlib.pyplot as plt
x = [1, 2, 3, 4, 5]
y1 = [2, 5, 8, 12, 9]
y2 = [10, 6, 2, 1, 6]
plt.plot(x, y1, marker='D')
# add second line here:
plt.show()
Python
Setting up Python environment...
Output