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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_jvm_opts(data, out_file):
 """Retrieve JVM options when running the Java version of VarDict. """

    if get_vardict_command(data) == "vardict-java":
        resources = config_utils.get_resources("vardict", data["config"])
        jvm_opts = resources.get("jvm_opts", ["-Xms750m", "-Xmx4g"])
        jvm_opts += broad.get_default_jvm_opts(os.path.dirname(out_file))
        return "export VAR_DICT_OPTS='%s' && " % " ".join(jvm_opts)
    else:
        return ""