just write the right hand side code, you have indicated (inplace=True) so you don't have to reassign it to the data object.

code to use:

\>>> data.drop(['label1','label2'],axis = 1, inplace = True)

\>>> data.head()

Output:

your data frame without lable1 & label 2

otherwise you'll delete your data frame completely and a None object will be assigned to your data frame object.