import numpy as np
import matplotlib.pyplot as plt
x = np.linspace(0, 2*np.pi, 100)
y = np.sin(x)
ax = plt.subplot(111)
ax.plot(x, y)
# Hide the right and top spines
ax.spines.right.set_visible(False)
ax.spines.top.set_visible(False)
# Only show ticks on the left and bottom spines
ax.yaxis.set_ticks_position('left')
ax.xaxis.set_ticks_position('bottom')
plt.show()