I have a data frame
df = pd.DataFrame({'Col1':['a','a','a','b','b','b','c','c','c'],
                  'Col2':[ '2020-12-01','2020-11-05','2019-01-05','2017-08-07',
                          '2018-07-16','2018-12-31','2019-11-30','2018-05-15',
                          '2019-01-15']})
I want the unique values in Col1 to be with most recent date Col2. The required column would be like this
    Col1  Col2 
0   a     2020-12-01
1   b     2018-12-31
2   c     2019-11-30
 
     
    