When one column of the dataframe is false, how can I assign True to the other column faster?

Question

As in the title, when the flag column is False, assign True to the flag2 column.

Is there an easier way in the follow line below?

df['flag2'] = df.flag == False

My code is as follows:

import pandas as pd

n1 = range(10)

df = pd.DataFrame(n1, columns=['data'])
df['flag'] = df.data > 5
df['flag2'] = df.flag == False

Answer 1

Use inverting by ~:

df['flag2'] = ~df.flag