Grid/__init__.py
def matrix2d_flip_horizontal(m, n, i, j):
    '''
    matrix2d_flip_horizontal
    ========================
    mirror the matrix coordinate across the vertical bisector.
    '''
    return (i, n -1 -j)

    matrix2d_flip_horizontal
    ========================
    mirror the matrix coordinate across the vertical bisector.
    
matrix2d_flip_horizontal
mirror the matrix coordinate across the vertical bisector.
matrix2d_flip_horizontal mirror the matrix coordinate across the vertical bisector .
def matrix2d_flip_horizontal(m, n, i, j):
    return (i, n -1 -j)
def matrix2d_flip_horizontal ( m , n , i , j ) : return ( i , n - 1 - j )
matrix2d_flip_horizontal
mirror the matrix coordinate across the vertical bisector.
matrix2d_flip_horizontal mirror the matrix coordinate across the vertical bisector .
'''
    matrix2d_flip_horizontal
    ========================
    mirror the matrix coordinate across the vertical bisector.
    '''
m
n
i
j