One solution with GridSpec (less elegant than jared's answer):

fig = plt.figure(figsize=(4,8)) 
gs = fig.add_gridspec(nrows=4, ncols=2, left=0.05, right=0.95, hspace=0.25, wspace=0.3)
ax0 = fig.add_subplot(gs[0:2, :])
ax1 = fig.add_subplot(gs[2, 0])
ax2 = fig.add_subplot(gs[2, 1])
ax3 = fig.add_subplot(gs[3, 0])
ax4 = fig.add_subplot(gs[3, 1])