I am trying to create a new data frame from an existing data frame with the count of existing columns in the data frame. Let's assume I have following DataFrame
| cus_Type | ID | ID_type | 
|---|---|---|
| R | 100 | X | 
| S | 100 | Y | 
| R | 101 | X | 
| S | 102 | Y | 
| P | 103 | X | 
| B | 104 | Y | 
| P | 105 | X | 
| B | 106 | Y | 
| K | 108 | D | 
I would like to create a new data Frame from the above with following 'count' of cus_Type ,ID_type like below:
| cus_Type | ID_type | count | 
|---|---|---|
| R | X | 2 | 
| S | Y | 2 | 
| P | X | 2 | 
| B | Y | 2 | 
| K | D | 1 | 
I am trying to use pd.groupby(['cus_Type','ID_type']) but not sure how to bring count as a new column in the existing data frame.