annotate, .
:
import matplotlib.pyplot as plt
fig = plt.figure()
ax = fig.add_subplot(1, 1, 1)
ax.annotate("TESTING", xy=(.5, .5), xytext=(.5, .5),
)
plt.show()

:
import matplotlib.pyplot as plt
fig = plt.figure()
ax = fig.add_subplot(1, 1, 1)
text = ax.annotate("TESTING", xy=(.5, .5), xytext=(.5, .5),
)
text.set_alpha(.4)
plt.show()
