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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_table_group(h5file, ifo=None):
 """Find the right `h5py.Group` within the given `h5py.File` """

    exclude = ('background',)
    if ifo is None:
        try:
            ifo, = [key for key in h5file if key not in exclude]
        except ValueError as exc:
            exc.args = ("PyCBC live HDF5 file contains dataset groups "
                        "for multiple interferometers, please specify "
                        "the prefix of the relevant interferometer via "
                        "the `ifo` keyword argument, e.g: `ifo=G1`",)
            raise
    try:
        return h5file[ifo], ifo
    except KeyError as exc:
        exc.args = ("No group for ifo %r in PyCBC live HDF5 file" % ifo,)
        raise