<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def dict_to_dom(root_node, xml_dict):
 """ Create a DOM node and optionally several subnodes from a dictionary. :param root_node: DOM-Node set the dictionary is applied upon :type root_node: xml.dom.Element :param xml_dict: The dictionary containing the nodes to process :type xml_dict: dict """


    if '_content' in list(xml_dict.keys()):

        root_node.appendChild(
            root_node.ownerDocument.createTextNode(
                convert_to_str(xml_dict['_content'])
            )
        )

    for key, value in xml_dict.items():

        if key == '_content':
            continue

        if type(value) == dict:

            # Root node

            tmp_node = root_node.ownerDocument.createElement(key)

            dict_to_dom(tmp_node, value)

            root_node.appendChild(tmp_node)

        elif type(value) == list:

            for multinode in value:

                tmp_node = root_node.ownerDocument.createElement(key)

                dict_to_dom(tmp_node, multinode)

                root_node.appendChild(tmp_node)

        else:

            # Attributes

            root_node.setAttribute(
                key,
                convert_to_str(value)
            )