def get_sandbox_virtualenv_path(pack: str) -> Optional[str]:
    """
    Return a path to the virtual environment for the provided pack.
    """

    if pack in SYSTEM_PACK_NAMES:
        virtualenv_path = None
    else:
        system_base_path = cfg.CONF.system.base_path
        virtualenv_path = str(os.path.join(system_base_path, "virtualenvs", pack))

    return virtualenv_path

    Return a path to the virtual environment for the provided pack.
    
st2common/st2common/util/sandboxing.py