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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 convert_missing_indexer(indexer):
 """ reverse convert a missing indexer, which is a dict return the scalar indexer and a boolean indicating if we converted """


    if isinstance(indexer, dict):

        # a missing key (but not a tuple indexer)
        indexer = indexer['key']

        if isinstance(indexer, bool):
            raise KeyError("cannot use a single bool to index into setitem")
        return indexer, True

    return indexer, False