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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 _create_counts(out_dts, out_dir):
 """Summarize results into single files."""

    ma, ma_mirna = _merge(out_dts)
    out_ma = op.join(out_dir, "counts.tsv")
    out_ma_mirna = op.join(out_dir, "counts_mirna.tsv")
    ma.to_csv(out_ma, sep="\t")
    ma_mirna.to_csv(out_ma_mirna, sep="\t")
    return out_ma_mirna, out_ma