fig, ax = plt.subplots()
fig.suptitle("City Statistics")
ax.set_ylabel("Population")
ax.set_xlabel("Citites")
ax2 = ax.twinx()
ax2.set_ylabel("Area")
city_frame["population"].plot(ax=ax,
style="b-",
use_index=True,
rot=90)
city_frame["area"].plot(ax=ax2,
style="g-",
use_index=True,
rot=90)