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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 _findSamesetProteins(protToPeps, proteins=None):
 """Find proteins that are mapped to an identical set of peptides. :param protToPeps: dict, for each protein (=key) contains a set of :param proteins: iterable, proteins that are tested for having equal evidence. If not specified all proteins are tested :returns: a list of sorted protein tuples that share equal peptide evidence """

    proteins = viewkeys(protToPeps) if proteins is None else proteins

    equalEvidence = ddict(set)
    for protein in proteins:
        peptides = protToPeps[protein]
        equalEvidence[tuple(sorted(peptides))].add(protein)
    equalProteins = list()
    for proteins in viewvalues(equalEvidence):
        if len(proteins) > 1:
            equalProteins.append(tuple(sorted(proteins)))
    return equalProteins