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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 _get_caller_supplement(caller, data):
 """Some callers like MuTect incorporate a second caller for indels. """

    if caller == "mutect":
        icaller = tz.get_in(["config", "algorithm", "indelcaller"], data)
        if icaller:
            caller = "%s/%s" % (caller, icaller)
    return caller