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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def point_on_line(point, line_start, line_end, accuracy=50.):
 """Checks whether a point lies on a line The function checks whether the point "point" (P) lies on the line defined by its starting point line_start (A) and its end point line_end (B). This is done by comparing the distance of [AB] with the sum of the distances [AP] and [PB]. If the difference is smaller than [AB] / accuracy, the point P is assumed to be on the line. By increasing the value of accuracy (the default is 50), the tolerance is decreased. :param point: Point to be checked (tuple with x any y coordinate) :param line_start: Starting point of the line (tuple with x any y coordinate) :param line_end: End point of the line (tuple with x any y coordinate) :param accuracy: The higher this value, the less distance is tolerated :return: True if the point is one the line, False if not """

    length = dist(line_start, line_end)
    ds = length / float(accuracy)
    if -ds < (dist(line_start, point) + dist(point, line_end) - length) < ds:
        return True

    return False