pandas dataframe check if index exists in a multi index

For this -

df

               0  1  2
userid itemid         
7      5000    9  4  3
       4000    6  7  1
9      3000    1  2  3

df.index.values
array([(7, 5000), (7, 4000), (9, 3000)], dtype=object)

You can use df.index.isin.

df.index.isin([(7, 5000)])
array([ True, False, False], dtype=bool)

This gives you a mask corresponding to where that value can be found. If you just want to know whether it exists or not, use np.ndarray.any in conjunction with isin.

df.index.isin([(7, 5000)]).any()
True

df.index.isin([(7, 6000)]).any()
False