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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 write_hdf5_dict(tsdict, h5f, group=None, **kwargs):
 """Write a `TimeSeriesBaseDict` to HDF5 Each series in the dict is written as a dataset in the group """

    # create group if needed
    if group and group not in h5f:
        h5g = h5f.create_group(group)
    elif group:
        h5g = h5f[group]
    else:
        h5g = h5f

    # write each timeseries
    kwargs.setdefault('format', 'hdf5')
    for key, series in tsdict.items():
        series.write(h5g, path=str(key), **kwargs)