Pandas Rolling String example

rolling_strings.py

import pandas as pd
import string 

df = pd.DataFrame([[*string.ascii_letters[0:26:2]],
                    *string.ascii_letters[1:26:2]])
rolled = df.rolling(window=2, center=False, axis=1).apply(lambda x: ''.join(x))

#expected: [['ac', 'ce', 'eg', 'gi', 'ik', 'km', 'mo', 'oq', 'qs', 'su', 'uw', 'wy'],
#            'bd', 'df', 'fh', 'hj', 'jl', 'ln', 'np', 'pr', 'rt', 'tv', 'vx', 'xz']]
print(rolled.values)
#is the original dataframe

not work...