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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 handle_multiple_callers(data, key, default=None, require_bam=True):
 """Split samples that potentially require multiple variant calling approaches. """

    callers = get_variantcaller(data, key, default, require_bam=require_bam)
    if isinstance(callers, six.string_types):
        return [data]
    elif not callers:
        return []
    else:
        out = []
        for caller in callers:
            base = copy.deepcopy(data)
            if not base["config"]["algorithm"].get("orig_%s" % key):
                base["config"]["algorithm"]["orig_%s" % key] = \
                  base["config"]["algorithm"][key]
            base["config"]["algorithm"][key] = caller
            # if splitting by variant caller, also split by jointcaller
            if key == "variantcaller":
                jcallers = get_variantcaller(data, "jointcaller", [])
                if isinstance(jcallers, six.string_types):
                    jcallers = [jcallers]
                if jcallers:
                    base["config"]["algorithm"]["orig_jointcaller"] = jcallers
                    jcallers = [x for x in jcallers if x.startswith(caller)]
                    if jcallers:
                        base["config"]["algorithm"]["jointcaller"] = jcallers[0]
                    else:
                        base["config"]["algorithm"]["jointcaller"] = False
            out.append(base)
        return out