python: assignment of zero to random cells in a pandas.DataFrame

I'm trying to assign 0 to random cells in one dimension pandas.DataFrame.
The following code is the best way to think about doing this, however, I think there may be a more orderly approach to this problem.

import numpy as np
import pandas like pd
of random import randint

df = pd.DataFrame (np.random.randint (20, size = (10, 1)), columns = list (& # 39; A & # 39;))
col_size = len (df.columns)
row_size = len (df.index)
df[df.columns[randint(0, col_size-1)]][randint(0, row_size-1)] = 0

Could someone review and suggest if this is a good approach or are there better ways to do it?