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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 linear_chirp(npts=2000):
 """ Generates a simple linear chirp. :param npts: Number of samples. :type npts: int :returns: Generated signal :rtype: numpy.ndarray """

    time = np.linspace(0, 20, npts)
    chirp = np.sin(0.2 * np.pi * (0.1 + 24.0 / 2.0 * time) * time)
    return chirp