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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 find_trigger_value(psd_var, idx, start, sample_rate):
 """ Find the PSD variation value at a particular time Parameters psd_var : TimeSeries Time series of the varaibility in the PSD estimation idx : numpy.ndarray Time indices of the triggers start : float GPS start time sample_rate : float Sample rate defined in ini file Returns ------- vals : Array PSD variation value at a particular time """


    # Find gps time of the trigger
    time = start + idx / sample_rate
    # Find where in the psd variation time series the trigger belongs
    ind = numpy.digitize(time, psd_var.sample_times)
    ind -= 1
    vals = psd_var[ind]
    return vals