How to use the owslib.etree.etree.Element function in OWSLib

def test_wps_process_with_invalid_identifer():
    p = Process(etree.Element('invalid'))
    assert repr(p) == ''
    assert str(p) == 'WPS Process: , title='

if elem.tag[0] == "{":
                uri, tag = elem.tag[1:].split("}")
                existing_namespaces.add(namespaces.get_namespace_from_url(uri))
        for key, link in ns_keys:
            if link is not None and key not in existing_namespaces:
                root.set("xmlns:%s" % key, link)
        return root
    else:
        # lxml does not support setting xmlns attributes
        # Update the elements nsmap with new namespaces
        new_map = root.nsmap
        for key, link in ns_keys:
            if link is not None:
                new_map[key] = link
        # Recreate the root element with updated nsmap
        new_root = etree.Element(root.tag, nsmap=new_map)
        # Carry over attributes
        for a, v in list(root.items()):
            new_root.set(a, v)
        # Carry over children
        for child in root:
            new_root.append(deepcopy(child))
        return new_root

def axml_category(d):
    # 
    if is_empty(d):
        return None
    else:
        try:
            category = etree.Element("category", nsmap=ns)
            term = extract_p('term', d, None)
            if term is not None: category.set("term", term)
            scheme = extract_p('scheme', d, None)
            if scheme is not None: category.set("scheme", scheme)
            label = extract_p('label', d, None)
            if label is not None: category.set("label", label)
            return category
        except Exception as ex:
            log.warn('could encode category', ex)
            return None

def axml_styleset(d):
    #     
    #       raster
    #       Default Raster
    #       A sample style that draws a 
    #       
    #     
    if is_empty(d):
        return None
    else:
        try:
            styleset = etree.Element(ns_elem("owc", "styleSet"), nsmap=ns)

            name = extract_p('name', d, None)
            if name is not None: etree.SubElement(styleset, ns_elem("owc", "name")).text = name
            title = extract_p('title', d, None)
            if title is not None: etree.SubElement(styleset, ns_elem("owc", "title")).text = title
            subtitle = extract_p('abstract', d, None)
            if subtitle is not None: etree.SubElement(styleset, ns_elem("owc", "abstract")).text = subtitle
            is_default = extract_p('default', d, None)
            # TODO no example for default setting on style set
            if is_default is not None: etree.SubElement(styleset, ns_elem("owc", "default")).text = is_default
            legend_url = extract_p('legendURL', d, None)
            if legend_url is not None: etree.SubElement(styleset, ns_elem("owc", "legendURL")).text = legend_url
            # TODO no example for content on style set
            content = extract_p('content', d, None)
            content_enc = None if content is None else axml_content(content)
            if content_enc is not None: styleset.append(content_enc)

def axml_creator_app(d):
    # MiraMon
    if is_empty(d):
        return None
    else:
        try:
            creator_app = etree.Element("generator", nsmap=ns)
            title = extract_p('title', d, None)
            if title is not None: creator_app.text = title
            uri = extract_p('uri', d, None)
            if uri is not None: creator_app.set("uri", uri)
            version = extract_p('version', d, None)
            if version is not None: creator_app.set("version", version)
            return creator_app
        except Exception as ex:
            log.warn('could encode creator_app', ex)
            return None

def axml_operation(d):
    #    ..
    # etree.SubElement(entry, ns_elem("owc", "offering"), name="blah").text = "some value1"
    if is_empty(d):
        return None
    else:
        try:
            operation = etree.Element(ns_elem("owc", "operation"), nsmap=ns)

            operations_code = extract_p('code', d, None)
            if operations_code is not None: operation.set("code", operations_code)
            http_method = extract_p('method', d, None)
            if http_method is not None: operation.set("method", http_method)
            mimetype = extract_p('type', d, None)
            if mimetype is not None: operation.set("type", mimetype)
            request_url = extract_p('href', d, None)
            if request_url is not None: operation.set("href", request_url)

            # use axml_content here
            request = extract_p('request', d, None)
            request_enc = None if request is None else axml_content(request)
            if request_enc is not None: operation.append(request_enc)
            # use axml_content here
            result = extract_p('result', d, None)

def getXml(self):
        root = etree.Element(nspath_eval('wps:Reference', namespaces),
                             attrib={nspath_eval("xlink:href", namespaces): self.url})
        if self.method:
            root.attrib['method'] = self.method
        bodyElement = etree.SubElement(
            root, nspath_eval('wps:Body', namespaces))
        getFeatureElement = etree.SubElement(
            bodyElement, nspath_eval('wfs:GetFeature', namespaces),
            attrib={"service": "WFS",
                    "version": "1.1.0",
                    "outputFormat": "text/xml; subtype=gml/3.1.1",
                    nspath_eval("xsi:schemaLocation", namespaces): "%s %s" % (namespaces['wfs'], WFS_SCHEMA_LOCATION)})

        #            
        #                the_geom
        #                STATE
        #                

def toXML(self):
        node0 = etree.Element(util.nspath_eval('ogc:PropertyIsLike', namespaces))
        node0.set('wildCard', self.wildCard)
        node0.set('singleChar', self.singleChar)
        node0.set('escapeChar', self.escapeChar)
        if not self.matchCase:
            node0.set('matchCase', 'false')
        etree.SubElement(node0, util.nspath_eval('ogc:PropertyName', namespaces)).text = self.propertyname
        etree.SubElement(node0, util.nspath_eval('ogc:Literal', namespaces)).text = self.literal
        return node0

def _setrootelement(self, el):
        if etree.__name__ == 'lxml.etree':  # apply nsmap
            return etree.Element(util.nspath_eval(el, namespaces), nsmap=namespaces)
        else:
            return etree.Element(util.nspath_eval(el, namespaces))