# importing pandas as pd
 import pandas as pd

 # creating a dataframe
 df = pd.DataFrame({'A': ['Jo', 'Bo', 'Mi'],
       'B': ['blabla (21/07/2009)blablabla', 'texttexttext 12/04/2010',
       'textextblalba 28/03/2019)(12 texttext']})

df = pd.DataFrame({'A': ['Jo', 'Bo', 'Mi'],
       'B': ['blabla (21/07/2009)blablabla', 'texttexttext 12/04/2010',
       'textextblalba 28/03/2019)(12 texttext'],
       'C': ['21/07/2009', '12/04/2010', '28/03/2019']})