def get_config_xml_head(head_xpath):
    """Get xml head string when config.
    Args:
        head_xpath: The string of xpath_key.
    Returns:
        xml_head_str: The xml head str.
    """
    xml_head_str = "<config>"
    for item in head_xpath.split("/")[1:]:
        xml_head_str = xml_head_str + "<" + item + ">"
    return xml_head_str