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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 get_batch_for_key(data):
 """Retrieve batch information useful as a unique key for the sample. """

    batches = _get_batches(data, require_bam=False)
    if len(batches) == 1:
        return batches[0]
    else:
        return tuple(batches)