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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 _read_record(self, f, blk, chans):
 """Read raw data from a single EDF channel. Parameters i_chan : int index of the channel to read begsam : int index of the first sample endsam : int index of the last sample Returns ------- numpy.ndarray A vector with the data as written on file, in 16-bit precision """

        dat_in_rec = empty((len(chans), self.max_smp))

        i_ch_in_dat = 0
        for i_ch in chans:
            offset, n_smp_per_chan = self._offset(blk, i_ch)

            f.seek(offset)
            x = fromfile(f, count=n_smp_per_chan, dtype=EDF_FORMAT)

            ratio = int(self.max_smp / n_smp_per_chan)
            dat_in_rec[i_ch_in_dat, :] = repeat(x, ratio)
            i_ch_in_dat += 1

        return dat_in_rec