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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 calc_segment_times(d):
 """ Helper function for set_pipeline to define segmenttimes list, given nsegments definition """


    # this casts to int (flooring) to avoid 0.5 int rounding issue. 
    stopdts = n.linspace(d['nskip']+d['t_overlap']/d['inttime'], d['nints'], d['nsegments']+1)[1:]   # nseg+1 assures that at least one seg made
    startdts = n.concatenate( ([d['nskip']], stopdts[:-1]-d['t_overlap']/d['inttime']) )
            
    segmenttimes = []
    for (startdt, stopdt) in zip(d['inttime']*startdts, d['inttime']*stopdts):
        starttime = qa.getvalue(qa.convert(qa.time(qa.quantity(d['starttime_mjd']+startdt/(24*3600),'d'),form=['ymd'], prec=9)[0], 's'))[0]/(24*3600)
        stoptime = qa.getvalue(qa.convert(qa.time(qa.quantity(d['starttime_mjd']+stopdt/(24*3600), 'd'), form=['ymd'], prec=9)[0], 's'))[0]/(24*3600)
        segmenttimes.append((starttime, stoptime))
    d['segmenttimes'] = n.array(segmenttimes)
    totaltimeread = 24*3600*(d['segmenttimes'][:, 1] - d['segmenttimes'][:, 0]).sum()            # not guaranteed to be the same for each segment
    d['readints'] = n.round(totaltimeread / (d['inttime']*d['nsegments'])).astype(int)
    d['t_segment'] = totaltimeread/d['nsegments']