pandas value_counts applied to each column

Question

I have a dataframe with numerous columns (≈30) from an external source (csv file) but several of them have no value or always the same. Thus, I would to see qui

Answer 1

Code like the following

df = pd.DataFrame(data=[[34, 'null', 'mark'], [22, 'null', 'mark'], [34, 'null', 'mark']], columns=["id", 'temp', 'name'], index=[1, 2, 3]) 
result2 = df.apply(pd.value_counts)
result2

will produce: