def slope(first_point, second_point):
    """
    Returns the slope between 2 points

    :param first_point: first point (x,y)
    :param second_point: second point (x,y)
    :return: the slope
    """
    return 0. if first_point[0] == second_point[0] else\
        ((float(first_point[1]) - float(second_point[1])) / (float(first_point[0]) - float(second_point[0])))