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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 to_bam(in_file, out_file, data):
 """Convert CRAM file into BAM. """

    if not utils.file_uptodate(out_file, in_file):
        with file_transaction(data, out_file) as tx_out_file:
            cmd = ["samtools", "view", "-O", "BAM", "-o", tx_out_file, in_file]
            do.run(cmd, "Convert CRAM to BAM")
    bam.index(out_file, data["config"])
    return out_file