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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_interchange_biomass_reactions(model, biomass=None):
 """ Return the set of all transport, boundary, and biomass reactions. These reactions are either pseudo-reactions, or incorporated to allow metabolites to pass between compartments. Some tests focus on purely metabolic reactions and hence exclude this set. Parameters model : cobra.Model The metabolic model under investigation. biomass : list or cobra.Reaction, optional A list of cobrapy biomass reactions. """

    boundary = set(model.boundary)
    transporters = find_transport_reactions(model)
    if biomass is None:
        biomass = set(find_biomass_reaction(model))
    return boundary | transporters | biomass