def TransferFunction(num:list[float], den:list[float], deadtime: float = 0.0, dt:float=0.0) -> control.TransferFunction:    """    Creates a discrete-time transfer function with the given numerator and     denominator coefficients.    Also adds deadtime to the transfer function if given.    Parameters    ----------    num : list        Numerator coefficients of the transfer function    den : list        Denominator coefficients of the transfer function    deadtime : float, optional        Deadtime of the transfer function, by default 0    dt : float, optional        Sampling time of the transfer function, by default 0.1        Returns    -------    control.TransferFunction        Discrete-time transfer function with the given parameters        Examples    --------    >>> import matplotlib.pyplot as plt    >>> num = [0.9958683]    >>> den = [1, -0.0041317]    >>> deadtime = 5    >>> dt = 0.5    >>> Gz = TransferFunction(num, den, deadtime, dt)    >>> print(Gz.dcgain)    >>> y, t = Gz.step_response    >>> plt.title('Stepresponse (Y per U)')    >>> plt.plot(t, y, '-r')    >>> plt.xlabel('Time(min)')    >>> plt.ylabel('Amplitude')    >>> plt.grid()    >>> plt.show()    """    if dt:        Gz = control.TransferFunction(num, den, dt)    else:        Gs = control.TransferFunction(num, den)        # dt = get_dt(Gs)        dt = 0.1        Gz = control.sample_system(Gs, dt, 'tustin')    if deadtime >= 1:        deadtime_samples = int(np.ceil(deadtime/dt)) + 1        theta = np.full(deadtime_samples, 0.0)        for i in range(len(theta)):            if i % 2 != 0:                theta[i] = -0.0        denz = np.concatenate((Gz.den[0][0].flatten(), theta), axis=None)        Gz.den[0][0] = denz    return Gz