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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_duplicate_metabolites_in_compartments(model):
 """ Return list of metabolites with duplicates in the same compartment. This function identifies duplicate metabolites in each compartment by determining if any two metabolites have identical InChI-key annotations. For instance, this function would find compounds with IDs ATP1 and ATP2 in the cytosolic compartment, with both having the same InChI annotations. Parameters model : cobra.Model The metabolic model under investigation. Returns ------- list A list of tuples of duplicate metabolites. """

    unique_identifiers = ["inchikey", "inchi"]
    duplicates = []
    for met_1, met_2 in combinations(model.metabolites, 2):
        if met_1.compartment == met_2.compartment:
            for key in unique_identifiers:
                if key in met_1.annotation and key in met_2.annotation:
                    if met_1.annotation[key] == met_2.annotation[key]:
                        duplicates.append((met_1.id, met_2.id))
                        break
    return duplicates