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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 run(bam_file, data, out_dir):
 """Run coverage QC analysis """

    out = dict()

    out_dir = utils.safe_makedir(out_dir)
    if dd.get_coverage(data) and dd.get_coverage(data) not in ["None"]:
        merged_bed_file = bedutils.clean_file(dd.get_coverage_merged(data), data, prefix="cov-", simple=True)
        target_name = "coverage"
    elif dd.get_coverage_interval(data) != "genome":
        merged_bed_file = dd.get_variant_regions_merged(data) or dd.get_sample_callable(data)
        target_name = "variant_regions"
    else:
        merged_bed_file = None
        target_name = "genome"

    avg_depth = cov.get_average_coverage(target_name, merged_bed_file, data)
    if target_name == "coverage":
        out_files = cov.coverage_region_detailed_stats(target_name, merged_bed_file, data, out_dir)
    else:
        out_files = []

    out['Avg_coverage'] = avg_depth

    samtools_stats_dir = os.path.join(out_dir, os.path.pardir, 'samtools')
    from bcbio.qc import samtools
    samtools_stats = samtools.run(bam_file, data, samtools_stats_dir)["metrics"]

    out["Total_reads"] = total_reads = int(samtools_stats["Total_reads"])
    out["Mapped_reads"] = mapped = int(samtools_stats["Mapped_reads"])
    out["Mapped_paired_reads"] = int(samtools_stats["Mapped_paired_reads"])
    out['Duplicates'] = dups = int(samtools_stats["Duplicates"])

    if total_reads:
        out["Mapped_reads_pct"] = 100.0 * mapped / total_reads
    if mapped:
        out['Duplicates_pct'] = 100.0 * dups / mapped

    if dd.get_coverage_interval(data) == "genome":
        mapped_unique = mapped - dups
    else:
        mapped_unique = readstats.number_of_mapped_reads(data, bam_file, keep_dups=False)
    out['Mapped_unique_reads'] = mapped_unique

    if merged_bed_file:
        ontarget = readstats.number_of_mapped_reads(
            data, bam_file, keep_dups=False, bed_file=merged_bed_file, target_name=target_name)
        out["Ontarget_unique_reads"] = ontarget
        if mapped_unique:
            out["Ontarget_pct"] = 100.0 * ontarget / mapped_unique
            out['Offtarget_pct'] = 100.0 * (mapped_unique - ontarget) / mapped_unique
            if dd.get_coverage_interval(data) != "genome":
                # Skip padded calculation for WGS even if the "coverage" file is specified
                # the padded statistic makes only sense for exomes and panels
                padded_bed_file = bedutils.get_padded_bed_file(out_dir, merged_bed_file, 200, data)
                ontarget_padded = readstats.number_of_mapped_reads(
                    data, bam_file, keep_dups=False, bed_file=padded_bed_file, target_name=target_name + "_padded")
                out["Ontarget_padded_pct"] = 100.0 * ontarget_padded / mapped_unique
        if total_reads:
            out['Usable_pct'] = 100.0 * ontarget / total_reads

    indexcov_files = _goleft_indexcov(bam_file, data, out_dir)
    out_files += [x for x in indexcov_files if x and utils.file_exists(x)]
    out = {"metrics": out}
    if len(out_files) > 0:
        out["base"] = out_files[0]
        out["secondary"] = out_files[1:]
    return out