In [8]:

    

import pandas as pd
import numpy as np

from dsutil.general import DataframeFunctionTransformer


    

In [9]:

    

df = pd.DataFrame({
    'name':['john','peter',np.nan],
    'age':[12,34,43]
})


    

In [12]:

    

trans=DataframeFunctionTransformer('name',lambda n: n.upper(),none_treatment='return_none')


    

In [13]:

    

trans.fit_transform(df)


    

    
Out[13]:







  

    

      

      
age
      
name
    
  
  

    

      
0
      
12
      
JOHN
    
    

      
1
      
34
      
PETER
    
    

      
2
      
43
      
NaN
    
  

In [ ]: