df= col1 col2 col3 col4.... col300
21 31 43 64 21
I want to get to
df= col1 col2 col5.... col300
21 31 27 21
df2= col3 col4
43 64
How can I do that with a large dataset? I want split the dataframe, or drop 2 of the columns as a separate dataframe?