How to extract non-consecutive rows and columns of a matrix?

How do I extract from a matrix rows and columns that are not consecutive. For example, in this matrix how do i extract rows 1,2 and 4 with columns 1, 2 and 4?

import numpy as np

a = np.matrix([[1, 2, 3, 4, 5],
               [6, 7, 8, 9, 10],
               [11, 12, 13, 14, 15],
               [16, 17, 18, 19, 20],
               [18, 19, 20, 21, 22]])

So the new matrix should be:

b = ([[7, 8 , 10],
     [12, 13, 15],
     [19, 20, 22]])

source https://stackoverflow.com/questions/71443487/how-to-extract-non-consecutive-rows-and-columns-of-a-matrix

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