Sorting arrays in NumPy by column

Question

How can I sort a numpy array with its nth column?

Consider this

a = array([[9, 2, 3],
           [4, 5, 6],
           [7, 0, 5]])

I want to sort rows of a by second column and get the output like this

array([[7, 0, 5],
       [9, 2, 3],
       [4, 5, 6]])