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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 _annotate_validations(eval_files, data):
 """Add annotations about potential problem regions to validation VCFs. """

    for key in ["tp", "tp-calls", "fp", "fn"]:
        if eval_files.get(key):
            eval_files[key] = annotation.add_genome_context(eval_files[key], data)
    return eval_files