How to use the webserver.web.template.TextNode function in webserver

name = tokens[1]
        sep = tokens[2]
        value = line.split(sep, 1)[1].strip()
        
        if sep == '=':
            pass # no need to process value
        elif sep == ':': 
            #@@ Hack for backward-compatability
            if tokens[3] == '\n': # multi-line var statement
                block, text = self.read_indented_block(text, '    ')
                lines = [self.readline(x)[0] for x in block.splitlines()]
                nodes = []
                for x in lines:
                    nodes.extend(x.nodes)
                    nodes.append(TextNode('\n'))         
            else: # single-line var statement
                linenode, _ = self.readline(value)
                nodes = linenode.nodes                
            parts = [node.emit('') for node in nodes]
            value = "join_(%s)" % ", ".join(parts)
        else:
            raise SyntaxError('Invalid var statement')
        return VarNode(name, value), text

def read_node(self, text):
        r"""Reads a node from the given text and returns the node and remaining text.

            >>> read_node = Parser('').read_node
            >>> read_node('hello $name')
            (t'hello ', '$name')
            >>> read_node('$name')
            ($name, '')
        """
        if text.startswith('$$'):
            return TextNode('$'), text[2:]
        elif text.startswith('$#'): # comment
            line, text = splitline(text)
            return TextNode('\n'), text
        elif text.startswith('$'):
            text = text[1:] # strip $
            if text.startswith(':'):
                escape = False
                text = text[1:] # strip :
            else:
                escape = True
            return self.read_expr(text, escape=escape)
        else:
            return self.read_text(text)

def read_text(self, text):
        r"""Reads a text node from the given text.
        
            >>> read_text = Parser('').read_text
            >>> read_text('hello $name')
            (t'hello ', '$name')
        """
        index = text.find('$')
        if index < 0:
            return TextNode(text), ''
        else:
            return TextNode(text[:index]), text[index:]

def read_node(self, text):
        r"""Reads a node from the given text and returns the node and remaining text.

            >>> read_node = Parser('').read_node
            >>> read_node('hello $name')
            (t'hello ', '$name')
            >>> read_node('$name')
            ($name, '')
        """
        if text.startswith('$$'):
            return TextNode('$'), text[2:]
        elif text.startswith('$#'): # comment
            line, text = splitline(text)
            return TextNode('\n'), text
        elif text.startswith('$'):
            text = text[1:] # strip $
            if text.startswith(':'):
                escape = False
                text = text[1:] # strip :
            else:
                escape = True
            return self.read_expr(text, escape=escape)
        else:
            return self.read_text(text)

def read_text(self, text):
        r"""Reads a text node from the given text.
        
            >>> read_text = Parser('').read_text
            >>> read_text('hello $name')
            (t'hello ', '$name')
        """
        index = text.find('$')
        if index < 0:
            return TextNode(text), ''
        else:
            return TextNode(text[:index]), text[index:]