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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 _has_bcftools_germline_stats(data):
 """Check for the presence of a germline stats file, CWL compatible. """

    stats_file = tz.get_in(["summary", "qc"], data)
    if isinstance(stats_file, dict):
        stats_file = tz.get_in(["variants", "base"], stats_file)
    if not stats_file:
        stats_file = ""
    return stats_file.find("bcftools_stats_germline") > 0