python – Why function sampled in time frequency is not repeating?

I’m reading my lecture and found this figure:
sampled signal in frequency domain

So, I get the continuous function after sampling, in frequency domain, should repeat the pattern of the original continuous function. But in my Python code I just get one square where it should be a
lot more squares repeating. I’m new to signals (I’m not engineer, it’s an additional course) so I’m a little confused with my code. Am I missing something? Sorry if it is something dumb or concept misunderstanding.

def g(t):
    if t == 0:
        return 1
    return np.sin(1.5*np.pi*t) / (1.5*np.pi*t)

if __name__ == '__main__':
    n = 40
    fs = 100  # 0.01
    t = np.arange(-n, n, 1.0/fs)
    y = [g(i) for i in t]

    plt.plot(t, y)
    plt.xlim(-5, 5)

        # Impulse train
    n = 40
    T = 1.0/2.5
    tn = np.arange(-n, n, T)
    # y2 = [1 for i in range(len(tn))]
    nT = tn*T
    y2 = [g(i) for i in nT]

    # Sampled g
    plt.stem(nT, y2, 'r', markerfmt="C3o", use_line_collection=True)
    plt.xlim(-0.9, 0.9)

    fft_s = fft(y2)
    plt.plot(fftshift(fftfreq(len(fft_s ))),
             fftshift(np.abs(fft_s )))

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