Os pandas substituem string por outra string
df['prod_type'] = df['prod_type'].replace({'respon':'responsive', 'r':'responsive'})
Smoking Snake
df['prod_type'] = df['prod_type'].replace({'respon':'responsive', 'r':'responsive'})>>> pd.Series(['foo', 'fuz', np.nan]).str.replace('f.', 'ba', regex=True)
0 bao
1 baz
2 NaN
dtype: object