Append the list of element names as a path to the provided start element.

    :return: The final element along the path.

def _element_append_path(
        start_element,  # type: ET.Element
        element_names  # type: Iterable[Text]
):
    # type: (...) -> ET.Element
    """
    Append the list of element names as a path to the provided start element.

    :return: The final element along the path.
    """
    end_element = start_element
    for element_name in element_names:
        new_element = ET.Element(element_name)
        end_element.append(new_element)
        end_element = new_element

    return end_element