Using a text file as the input for a program : <p>In a program, you can simulate a magic square by using a two-dimensional list. Write a Python program that tests whether or not a 3 by 3 grid is a valid magic square. The program reads the input from a text file named input.txt. Each line in the file contains exactly 9 numbers that correspond to the the second row, and the last three values correspond to the last row. </p>

<p>I am not struggling with how to create the program to check to see if the square is a magic square, but how do I read in the "input.txt" into the program when I run it?</p>
