def reshape_coord(center_contours):
    """ Decomposes list of (x,y) into 2 x and y lists, as follows
        [ 'xi, yi', 'xi+1, yi+1', 'xn, yn'] -> [xi, xi+1, xn] & [yi, yi+1, yn]
    """
    x, y = [], []
    for i, j in enumerate(center_contours[:-1]):
        x.append(j[0])
        y.append(j[1])
    return x, y