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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 _flattenMergedProteins(proteins):
 """Return a set where merged protein entries in proteins are flattened. :param proteins: an iterable of proteins, can contain merged protein entries in the form of tuple([protein1, protein2]). returns a set of protein entries, where all entries are strings """

    proteinSet = set()
    for protein in proteins:
        if isinstance(protein, tuple):
            proteinSet.update(protein)
        else:
            proteinSet.add(protein)
    return proteinSet