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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 _clean_annotations(annotations_dict: AnnotationsHint) -> AnnotationsDict: """Fix the formatting of annotation dict."""

    return {
        key: (
            values if isinstance(values, dict) else
            {v: True for v in values} if isinstance(values, set) else
            {values: True}
        )
        for key, values in annotations_dict.items()
    }