Define a function first$\_$rpt$($M$)$ which takes as input a NumPy matrix M$,$ and outputs a matrix in which every row of M has been replaced with the first row.

For example, the output of first$\_$rpt$($my$\_$matrix$),$ where my$\_$matrix is given by

my$\_$matrix$=$np$.$array$([[1,2,3,4],[-5,-6,-7,-8],[1,5,2,3]])$

should be the matrix

array$([[1,2,3,4],$

$[1,2,3,4],$

$[1,2,3,4]])$