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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 _get_columns(h5group):
 """Find valid column names from a PyCBC HDF5 Group Returns a `set` of names. """

    columns = set()
    for name in sorted(h5group):
        if (not isinstance(h5group[name], h5py.Dataset) or
                name == 'template_boundaries'):
            continue
        if name.endswith('_template') and name[:-9] in columns:
            continue
        columns.add(name)
    return columns - META_COLUMNS