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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_sv_callers(items):
 """ return a sorted list of all of the structural variant callers run """

    callers = []
    for data in items:
        for sv in data.get("sv", []):
            callers.append(sv["variantcaller"])
    return list(set([x for x in callers if x != "sv-ensemble"])).sort()