Python Trimming a few column names but not all in a dataframe

Question

I have a dataframe of many columns. Now I am trimming a few columns to reduce the text length.

Code:

xdf = pd.DataFrame({'Column1':[10,25],'Column2':[10,25],'Fix_col':[10,25]})

## Rename `Column1` to `C1` and for `C2` as well
req_cols = ['Column1','Column2']

xdf[req_cols].columns = [x[0]+y for name in xdf[req_cols].str.findall(r'([A-Za-z]+)(\d+)' for x,y in name]

Present solution:

print([x[0]+y for name in xdf[req_cols].str.findall(r'([A-Za-z]+)(\d+)' for x,y in name])
['C1','C2']
print(xdf[req_cols].columns)
['Column1','Column2']

Column names did not change. Don't know why?

Expected Answer:

xdf.columns = ['C1','C2','Fix_col']