import pandas as pd
 import numpy as np
 df = pd.DataFrame(np.random.randint(10,99,size=(10,5)))
 df.iloc[4:6,0] = np.nan
 df.iloc[5:7,2] = np.nan
 df.iloc[7,3] = np.nan
 df.iloc[2:3,4] = np.nan

    0  1   2   3   4
 0 63.0 89 58.0 94.0 10.0
 1 44.0 77 66.0 54.0 14.0
 2 25.0 41 93.0 56.0  NaN
 3 43.0 26 27.0 53.0 44.0
 4  NaN 98 45.0 32.0 45.0
 5  NaN 28  NaN 72.0 10.0
 6 69.0 92  NaN 24.0 61.0
 7 51.0 22 35.0  NaN 72.0
 8 83.0 32 93.0 62.0 25.0
 9 48.0 54 83.0 30.0 79.0

df.isnull()

    0   1   2   3   4
 0 False False False False False
 1 False False False False False
 2 False False False False  True
 3 False False False False False
 4  True False False False False
 5  True False  True False False
 6 False False  True False False
 7 False False False  True False
 8 False False False False False
 9 False False False False False

df.isnull().any()

 0   True
 1  False
 2   True
 3   True
 4   True
dtype: bool

df.isnull().sum()

 0  2
 1  0
 2  2
 3  1
 4  1
 dtype: int64