How to use the nbxmpp.simplexml.Node function in nbxmpp

if hash_data:
                    file_tag.addChild(node=hash_data)
                pjid = app.get_jid_without_resource(self.session.peerjid)
                file_info = {'name' : self.file_props.name,
                             'file-name' : self.file_props.file_name,
                             'hash' : self.file_props.hash_,
                             'size' : self.file_props.size,
                             'date' : self.file_props.date,
                             'peerjid' : pjid
                            }
                self.session.connection.get_module('Jingle').set_file_info(file_info)
        desc = file_tag.setTag('desc')
        if self.file_props.desc:
            desc.setData(self.file_props.desc)
        if self.use_security:
            security = nbxmpp.simplexml.Node(
                tag=Namespace.JINGLE_XTLS + ' security')
            certpath = os.path.join(
                configpaths.get('MY_CERT'), SELF_SIGNED_CERTIFICATE) + '.cert'
            cert = load_cert_file(certpath)
            if cert:
                digest_algo = (cert.get_signature_algorithm()
                               .decode('utf-8').split('With')[0])
                security.addChild('fingerprint').addData(cert.digest(
                    digest_algo).decode('utf-8'))
                for m in ('x509', ): # supported authentication methods
                    method = nbxmpp.simplexml.Node(tag='method')
                    method.setAttr('name', m)
                    security.addChild(node=method)
                content.addChild(node=security)
        content.addChild(node=description_node)

desc = file_tag.setTag('desc')
        if self.file_props.desc:
            desc.setData(self.file_props.desc)
        if self.use_security:
            security = nbxmpp.simplexml.Node(
                tag=Namespace.JINGLE_XTLS + ' security')
            certpath = os.path.join(
                configpaths.get('MY_CERT'), SELF_SIGNED_CERTIFICATE) + '.cert'
            cert = load_cert_file(certpath)
            if cert:
                digest_algo = (cert.get_signature_algorithm()
                               .decode('utf-8').split('With')[0])
                security.addChild('fingerprint').addData(cert.digest(
                    digest_algo).decode('utf-8'))
                for m in ('x509', ): # supported authentication methods
                    method = nbxmpp.simplexml.Node(tag='method')
                    method.setAttr('name', m)
                    security.addChild(node=method)
                content.addChild(node=security)
        content.addChild(node=description_node)

def _fill_content(self, content):
        description_node = nbxmpp.simplexml.Node(
            tag=Namespace.JINGLE_FILE_TRANSFER_5 + ' description')
        file_tag = description_node.setTag('file')
        if self.file_props.name:
            node = nbxmpp.simplexml.Node(tag='name')
            node.addData(self.file_props.name)
            file_tag.addChild(node=node)
        if self.file_props.date:
            node = nbxmpp.simplexml.Node(tag='date')
            node.addData(self.file_props.date)
            file_tag.addChild(node=node)
        if self.file_props.size:
            node = nbxmpp.simplexml.Node(tag='size')
            node.addData(self.file_props.size)
            file_tag.addChild(node=node)
        if self.file_props.type_ == 'r':
            if self.file_props.hash_:
                file_tag.addChild('hash', attrs={'algo': self.file_props.algo},
                                  namespace=Namespace.HASHES_2,
                                  payload=self.file_props.hash_)
        else:

def _fill_content(self, content):
        description_node = nbxmpp.simplexml.Node(
            tag=Namespace.JINGLE_FILE_TRANSFER_5 + ' description')
        file_tag = description_node.setTag('file')
        if self.file_props.name:
            node = nbxmpp.simplexml.Node(tag='name')
            node.addData(self.file_props.name)
            file_tag.addChild(node=node)
        if self.file_props.date:
            node = nbxmpp.simplexml.Node(tag='date')
            node.addData(self.file_props.date)
            file_tag.addChild(node=node)
        if self.file_props.size:
            node = nbxmpp.simplexml.Node(tag='size')
            node.addData(self.file_props.size)
            file_tag.addChild(node=node)
        if self.file_props.type_ == 'r':
            if self.file_props.hash_:

def _fill_content(self, content):
        description_node = nbxmpp.simplexml.Node(
            tag=Namespace.JINGLE_FILE_TRANSFER_5 + ' description')
        file_tag = description_node.setTag('file')
        if self.file_props.name:
            node = nbxmpp.simplexml.Node(tag='name')
            node.addData(self.file_props.name)
            file_tag.addChild(node=node)
        if self.file_props.date:
            node = nbxmpp.simplexml.Node(tag='date')
            node.addData(self.file_props.date)
            file_tag.addChild(node=node)
        if self.file_props.size:
            node = nbxmpp.simplexml.Node(tag='size')
            node.addData(self.file_props.size)
            file_tag.addChild(node=node)
        if self.file_props.type_ == 'r':
            if self.file_props.hash_:
                file_tag.addChild('hash', attrs={'algo': self.file_props.algo},
                                  namespace=Namespace.HASHES_2,
                                  payload=self.file_props.hash_)
        else:
            # if the file is less than 10 mb, then it is small
            # lets calculate it right away
            if self.file_props.size < 10000000 and not self.file_props.hash_:
                hash_data = self._compute_hash()