How do I produce a subplots of different sizes side by size?

Question

import matplotlib.pyplot as plt
import matplotlib.gridspec as gridspec_kw

# plot it
f, (a0, a1, a2) = plt.subplots(3, 1, gridspec_kw={'height_ratios': [1, 1, 2]})

a0.plot(x, y)
a1.plot(x, y)
a2.plot(x, y)

f.tight_layout()

I am trying to produce a graph as above, however, I want to put the 2 smaller height (same length) graphs that are on top, to the right side of the bigger graph. How do I do that?

It should look something as above. (but just 2 smaller instead 5 smaller graphs)