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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 open(self, mode):
 """ Open the underlying .hdf5 file and the parent, if any """

        if self.hdf5 == ():  # not already open
            kw = dict(mode=mode, libver='latest')
            if mode == 'r':
                kw['swmr'] = True
            try:
                self.hdf5 = hdf5.File(self.filename, **kw)
            except OSError as exc:
                raise OSError('%s in %s' % (exc, self.filename))