def main():
    # Поучаем ось
    metro_signal, axis, ideal = get_metro_and_axis()
    T1 = 7
    T2 = 20.0
    v0 = [T1, T2]  # Initial parameter value
    v_result = run_approximation(metro_signal, axis, v0, e)

    # Plotting
    x = axis.get_axis()
    plot(x, metro_signal, "b")
    plot(x, wrapper_for_finding_2l(v_result, x), "g")
    grid()
    show()
def e(v, x, y):
    """ Error function. Очень важная. """
    return (wrapper_for_finding_2l(v,x)-y)