How do I plot a pie chart using Pandas with this data

You can plot directly with pandas selecting pie chart:

import pandas as pd
import matplotlib.pyplot as plt

df = pd.DataFrame({'Sex': ['female', 'male', 'female'], 'Smoke': [1, 3, 1]})

df.Smoke.groupby(df.Sex).sum().plot(kind='pie')
plt.axis('equal')
plt.show()

Say you start with:

import pandas as pd
from matplotlib.pyplot import pie, axis, show

df = pd.DataFrame({
    'Sex': ['female', 'male', 'female'],
    'Smoke': [1, 1, 1]})

You can always do something like this:

sums = df.Smoke.groupby(df.Sex).sum()
axis('equal');
pie(sums, labels=sums.index);
show()