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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(config, tmp_dir):
 """Retrieve common options for running VarScan. Handles jvm_opts, setting user and country to English to avoid issues with different locales producing non-compliant VCF. """

    resources = config_utils.get_resources("varscan", config)
    jvm_opts = resources.get("jvm_opts", ["-Xmx750m", "-Xmx2g"])
    jvm_opts = config_utils.adjust_opts(jvm_opts,
                                        {"algorithm": {"memory_adjust":
                                                       {"magnitude": 1.1, "direction": "decrease"}}})
    jvm_opts += ["-Duser.language=en", "-Duser.country=US"]
    jvm_opts += broad.get_default_jvm_opts(tmp_dir)
    return " ".join(jvm_opts)