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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_representative_batch(merged):
 """Prepare dictionary matching batch items to a representative within a group. """

    out = {}
    for mgroup in merged:
        mgroup = sorted(list(mgroup))
        for x in mgroup:
            out[x] = mgroup[0]
    return out