python pandas dataframe string manipulation inplace replace code example

Example 1: pandas replace word begins with contains

df['sport'] = df.sport.str.replace(r'(^.*ball.*$)', 'ball sport')
df

Example 2: str replace pandas

>>> pd.Series(['foo', 'fuz', np.nan]).str.replace('f.', 'ba', regex=True)
0    bao
1    baz
2    NaN
dtype: object