I have a dataframe:

```
df = pd.DataFrame({'date': ['2013-04-01','2013-04-01','2013-04-01','2013-04-02', '2013-04-02'],
           'month': ['1','1','3','3','5'],
          'pmonth': ['1', '1', '2', '5', '5'],
          'duration': [30, 15, 20, 15, 30],
         'pduration': ['10', '20', '30', '40', '50']})

```

I have to divide `duration` and `pduration` by value column of second dataframe where date and month of two `df` match. The second `df` is:

```
 df = pd.DataFrame({'date': ['2013-04-01','2013-04-02','2013-04-03','2013-04-04', '2013-04-05'],
           'month': ['1','1','3','3','5'],
          'value': ['1', '1', '2', '5', '5'],
          })

```

The second `df` is grouped by date and month, so duplicate combination of date month won't be present in the second `df`.