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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 convert_sbml_model(model):
 """Convert raw SBML model to extended model. Args: model: :class:`NativeModel` obtained from :class:`SBMLReader`. """

    biomass_reactions = set()
    for reaction in model.reactions:
        # Extract limits
        if reaction.id not in model.limits:
            lower, upper = parse_flux_bounds(reaction)
            if lower is not None or upper is not None:
                model.limits[reaction.id] = reaction.id, lower, upper

        # Detect objective
        objective = parse_objective_coefficient(reaction)
        if objective is not None and objective != 0:
            biomass_reactions.add(reaction.id)

    if len(biomass_reactions) == 1:
        model.biomass_reaction = next(iter(biomass_reactions))

    # Convert model to mutable entries
    convert_model_entries(model)

    # Detect extracelluar compartment
    if model.extracellular_compartment is None:
        extracellular = detect_extracellular_compartment(model)
        model.extracellular_compartment = extracellular

    # Convert exchange reactions to exchange compounds
    convert_exchange_to_compounds(model)