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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 list_species(model, seeds=None):
 """This function is deprecated."""

    seeds = None or []

    from ecell4_base.core import Species

    if not isinstance(seeds, list):
        seeds = list(seeds)

    expanded = model.expand([Species(serial) for serial in seeds])
    species_list = [sp.serial() for sp in expanded.list_species()]
    species_list = sorted(set(seeds + species_list))
    return species_list