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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 compute_hr(sig_len, qrs_inds, fs):
 """ Compute instantaneous heart rate from peak indices. Parameters sig_len : int The length of the corresponding signal qrs_inds : numpy array The qrs index locations fs : int, or float The corresponding signal's sampling frequency. Returns ------- heart_rate : numpy array An array of the instantaneous heart rate, with the length of the corresponding signal. Contains numpy.nan where heart rate could not be computed. """

    heart_rate = np.full(sig_len, np.nan, dtype='float32')

    if len(qrs_inds) < 2:
        return heart_rate

    for i in range(0, len(qrs_inds)-2):
        a = qrs_inds[i]
        b = qrs_inds[i+1]
        c = qrs_inds[i+2]
        rr = (b-a) * (1.0 / fs) * 1000
        hr = 60000.0 / rr
        heart_rate[b+1:c+1] = hr

    heart_rate[qrs_inds[-1]:] = heart_rate[qrs_inds[-1]]

    return heart_rate