def set_virtualenv_prefix(prefix_tuple):
    """
    :return: Sets the virtualenv prefix given a tuple returned from get_virtualenv_prefix()
    """
    if prefix_tuple[0] == "sys.real_prefix" and hasattr(sys, "real_prefix"):
        sys.real_prefix = prefix_tuple[1]
    elif prefix_tuple[0] == "sys.base_prefix" and hasattr(sys, "base_prefix"):
        sys.base_prefix = prefix_tuple[1]

    :return: Sets the virtualenv prefix given a tuple returned from get_virtualenv_prefix()
    
st2common/st2common/util/sandboxing.py