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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 metabolites_per_compartment(model, compartment_id):
 """ Identify all metabolites that belong to a given compartment. Parameters model : cobra.Model The metabolic model under investigation. compartment_id : string Model specific compartment identifier. Returns ------- list List of metabolites belonging to a given compartment. """

    return [met for met in model.metabolites
            if met.compartment == compartment_id]