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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 _evaluate_one(caller, svtype, size_range, ensemble, truth, data):
 """Compare a ensemble results for a caller against a specific caller and SV type. """

    def cnv_matches(name):
        return cnv_to_event(name, data) == svtype
    def is_breakend(name):
        return name.startswith("BND")
    def in_size_range(max_buffer=0):
        def _work(feat):
            minf, maxf = size_range
            buffer = min(max_buffer, int(((maxf + minf) / 2.0) / 10.0))
            size = feat.end - feat.start
            return size >= max([0, minf - buffer]) and size < maxf + buffer
        return _work
    def is_caller_svtype(feat):
        for name in feat.name.split(","):
            if ((name.startswith(svtype) or cnv_matches(name) or is_breakend(name))
                  and (caller == "sv-ensemble" or name.endswith(caller))):
                return True
        return False
    minf, maxf = size_range
    efeats = pybedtools.BedTool(ensemble).filter(in_size_range(0)).filter(is_caller_svtype).saveas().sort().merge()
    tfeats = pybedtools.BedTool(truth).filter(in_size_range(0)).sort().merge().saveas()
    etotal = efeats.count()
    ttotal = tfeats.count()
    match = efeats.intersect(tfeats, u=True).sort().merge().saveas().count()
    return {"sensitivity": _stat_str(match, ttotal),
            "precision": _stat_str(match, etotal)}