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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 chirp_stimul():
 """ Amplitude modulated chirp signal """

    from scipy.signal import chirp, hilbert
    duration = 1.0
    fs = 256
    samples = int(fs * duration)
    t = np.arange(samples) / fs
    signal = chirp(t, 20.0, t[-1], 100.0)
    signal *= (1.0 + 0.5 * np.sin(2.0 * np.pi * 3.0 * t))
    analytic_signal = hilbert(signal) * 0.5
    ref_abs = np.abs(analytic_signal)
    ref_instantaneous_phase = np.angle(analytic_signal)
    return analytic_signal, ref_abs, ref_instantaneous_phase