def ranked_vaccine_peptides(variant_to_vaccine_peptides_dict):
    """
    This function returns a sorted list whose first element is a Variant and whose second
    element is a list of VaccinePeptide objects.

    Parameters
    ----------
    variant_to_vaccine_peptides_dict : dict
        Dictionary from varcode.Variant to list of VaccinePeptide

    Returns list of (varcode.Variant, VaccinePeptide list) tuples
    """
    result_list = list(variant_to_vaccine_peptides_dict.items())

    def sort_key(variant_and_vaccine_peptides_pair):
        vaccine_peptides = variant_and_vaccine_peptides_pair[1]
        if len(vaccine_peptides) == 0:
            return 0.0
        else:
            top_vaccine_peptide = vaccine_peptides[0]
            return top_vaccine_peptide.combined_score

    # sort in descending order of combined (expression * mhc binding) scores
    result_list.sort(key=sort_key, reverse=True)
    return result_list