Design a Matrix class in Pyhton (WITHOUT using built in functions such as numpy):

- add(Matrix M). Tell a matrix to add M to itself and return a new matrix containing the result.

- mult(Matrix M). Tell a matrix to multiply itself by M and return a new matrix containing the result.

- scalarMult(float c). Tell a matrix to multiply itself by scalar c and return a new matrix containing the result.

- isZero(). Ask a matrix whether it is the zero matrix; return True if it is and False if not.

- isSquare(). Ask a matrix whether it is a square matrix; return True if is and false if not.

- __init__(rows, cols, elts). This is a so-called "constructor," i.e., a method that initializes a newly created matrix object. Every Python class should have a method with this name to initialize objects. In our case, the constructor has the number of rows and columns in the matrix as arguments, along with a list of the values to place in the matrix. This list is in "row-major order," meaning that it starts with all the elements of the first row, followed by all the elements of the second row, and so forth.