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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_active_vcinfo(data, use_ensemble=True):
 """Use first caller if ensemble is not active """

    active_vs = _get_variants(data)
    if len(active_vs) > 0:
        e_active_vs = []
        if use_ensemble:
            e_active_vs = [v for v in active_vs if v.get("variantcaller") == "ensemble"]
        if len(e_active_vs) == 0:
            e_active_vs = [v for v in active_vs if v.get("variantcaller") != "ensemble"]
        if len(e_active_vs) > 0:
            return e_active_vs[0]