Return the column name(s) for a specific value in a pandas dataframe

Question

where I have found this option in other languages such as R or SQL but I am not quite sure how to go about this in Pandas.

So I have a file with 1262 columns and 1 r

Answer 1

just for the sake of throwing something a bit different into the ring:

row = df.iloc[0]
row.reset_index().set_index(0).loc[38.15]