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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 strain(self, ifo, duration=32, sample_rate=4096):
 """ Return strain around the event Currently this will return the strain around the event in the smallest format available. Selection of other data is not yet available. Parameters ifo: str The name of the observatory you want strain for. Ex. H1, L1, V1 Returns ------- strain: pycbc.types.TimeSeries Strain around the event. """

        from astropy.utils.data import download_file
        from pycbc.frame import read_frame

        # Information is currently wrong on GWOSC!
        # channels = self.data['files']['FrameChannels']
        # for channel in channels:
        #    if ifo in channel:
        #        break

        length = "{}sec".format(duration)
        if sample_rate == 4096:
            sampling = "4KHz"
        elif sample_rate == 16384:
            sampling = "16KHz"

        channel = "{}:GWOSC-{}_R1_STRAIN".format(ifo, sampling.upper())
        url = self.data['files'][ifo][length][sampling]['GWF']
        filename = download_file(url, cache=True)
        return read_frame(str(filename), str(channel))