How to use the mwparserfromhell.parser.tokens function in mwparserfromhell

def _handle_attribute(self, start):
        """Handle a case where a tag attribute is at the head of the tokens."""
        name = quotes = None
        self._push()
        while self._tokens:
            token = self._tokens.pop()
            if isinstance(token, tokens.TagAttrEquals):
                name = self._pop()
                self._push()
            elif isinstance(token, tokens.TagAttrQuote):
                quotes = token.char
            elif isinstance(token, (tokens.TagAttrStart, tokens.TagCloseOpen,
                                    tokens.TagCloseSelfclose)):
                self._tokens.append(token)
                if name:
                    value = self._pop()
                else:
                    name, value = self._pop(), None
                return Attribute(name, value, quotes, start.pad_first,
                                 start.pad_before_eq, start.pad_after_eq)
            else:
                self._write(self._handle_token(token))
        raise ParserError("_handle_attribute() missed a close token")

def _handle_attribute(self, start):
        """Handle a case where a tag attribute is at the head of the tokens."""
        name = quotes = None
        self._push()
        while self._tokens:
            token = self._tokens.pop()
            if isinstance(token, tokens.TagAttrEquals):
                name = self._pop()
                self._push()
            elif isinstance(token, tokens.TagAttrQuote):
                quotes = token.char
            elif isinstance(token, (tokens.TagAttrStart, tokens.TagCloseOpen,
                                    tokens.TagCloseSelfclose)):
                self._tokens.append(token)
                if name:
                    value = self._pop()
                else:
                    name, value = self._pop(), None
                return Attribute(name, value, quotes, start.pad_first,
                                 start.pad_before_eq, start.pad_after_eq)
            else:
                self._write(self._handle_token(token))
        raise ParserError("_handle_attribute() missed a close token")

# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.


from . import tokens, ParserError
from ..nodes import (Argument, Comment, ExternalLink, Heading, HTMLEntity, Tag,
                     Template, Text, Wikilink)
from ..nodes.extras import Attribute, Parameter
from ..smart_list import SmartList
from ..wikicode import Wikicode

__all__ = ["Builder"]

_HANDLERS = {
    tokens.Text: lambda self, token: Text(token.text)
}

def _add_handler(token_type):
    """Create a decorator that adds a handler function to the lookup table."""
    def decorator(func):
        """Add a handler function to the lookup table."""
        _HANDLERS[token_type] = func
        return func
    return decorator


class Builder:
    """Builds a tree of nodes out of a sequence of tokens.

    To use, pass a list of :class:`.Token`\\ s to the :meth:`build` method. The
    list will be exhausted as it is parsed and a :class:`.Wikicode` object

    @_add_handler(tokens.ExternalLinkOpen)
    def _handle_external_link(self, token):
        """Handle when an external link is at the head of the tokens."""
        brackets, url = token.brackets, None
        self._push()
        while self._tokens:
            token = self._tokens.pop()
            if isinstance(token, tokens.ExternalLinkSeparator):
                url = self._pop()
                self._push()
            elif isinstance(token, tokens.ExternalLinkClose):
                if url is not None:
                    return ExternalLink(url, self._pop(), brackets)
                return ExternalLink(self._pop(), brackets=brackets)
            else:
                self._write(self._handle_token(token))
        raise ParserError("_handle_external_link() missed a close token")

def _handle_attribute(self, start):
        """Handle a case where a tag attribute is at the head of the tokens."""
        name = quotes = None
        self._push()
        while self._tokens:
            token = self._tokens.pop()
            if isinstance(token, tokens.TagAttrEquals):
                name = self._pop()
                self._push()
            elif isinstance(token, tokens.TagAttrQuote):
                quotes = token.char
            elif isinstance(token, (tokens.TagAttrStart, tokens.TagCloseOpen,
                                    tokens.TagCloseSelfclose)):
                self._tokens.append(token)
                if name:
                    value = self._pop()
                else:
                    name, value = self._pop(), None
                return Attribute(name, value, quotes, start.pad_first,
                                 start.pad_before_eq, start.pad_after_eq)
            else:
                self._write(self._handle_token(token))
        raise ParserError("_handle_attribute() missed a close token")

    @_add_handler(tokens.ArgumentOpen)
    def _handle_argument(self, token):
        """Handle a case where an argument is at the head of the tokens."""
        name = None
        self._push()
        while self._tokens:
            token = self._tokens.pop()
            if isinstance(token, tokens.ArgumentSeparator):
                name = self._pop()
                self._push()
            elif isinstance(token, tokens.ArgumentClose):
                if name is not None:
                    return Argument(name, self._pop())
                return Argument(self._pop())
            else:
                self._write(self._handle_token(token))
        raise ParserError("_handle_argument() missed a close token")

def _handle_wikilink(self, token):
        """Handle a case where a wikilink is at the head of the tokens."""
        title = None
        self._push()
        while self._tokens:
            token = self._tokens.pop()
            if isinstance(token, tokens.WikilinkSeparator):
                title = self._pop()
                self._push()
            elif isinstance(token, tokens.WikilinkClose):
                if title is not None:
                    return Wikilink(title, self._pop())
                return Wikilink(self._pop())
            else:
                self._write(self._handle_token(token))
        raise ParserError("_handle_wikilink() missed a close token")

def _handle_parameter(self, default):
        """Handle a case where a parameter is at the head of the tokens.

        *default* is the value to use if no parameter name is defined.
        """
        key = None
        showkey = False
        self._push()
        while self._tokens:
            token = self._tokens.pop()
            if isinstance(token, tokens.TemplateParamEquals):
                key = self._pop()
                showkey = True
                self._push()
            elif isinstance(token, (tokens.TemplateParamSeparator,
                                    tokens.TemplateClose)):
                self._tokens.append(token)
                value = self._pop()
                if key is None:
                    key = Wikicode(SmartList([Text(str(default))]))
                return Parameter(key, value, showkey)
            else:
                self._write(self._handle_token(token))
        raise ParserError("_handle_parameter() missed a close token")

    @_add_handler(tokens.CommentStart)
    def _handle_comment(self, token):
        """Handle a case where an HTML comment is at the head of the tokens."""
        self._push()
        while self._tokens:
            token = self._tokens.pop()
            if isinstance(token, tokens.CommentEnd):
                contents = self._pop()
                return Comment(contents)
            else:
                self._write(self._handle_token(token))
        raise ParserError("_handle_comment() missed a close token")

# templates. We can then build the parser tree out of those as usual, which
    # is a more expensive operation.
    reduced_tokens = []
    prev_section_idx = 0
    section_has_citation_needed = False
    for i, (t1, t2) in enumerate(zip(tokens, tokens[1:])):
        if isinstance(t2, mwparserfromhell.parser.tokens.HeadingStart):
            if section_has_citation_needed:
                reduced_tokens.extend(tokens[prev_section_idx:i+1])
            prev_section_idx = i+1
            section_has_citation_needed = False

        # We detect a citation needed template by looking at a TemplateOpen
        # token followed by a suitable Text token
        section_has_citation_needed |= (
            isinstance(t1, mwparserfromhell.parser.tokens.TemplateOpen) and
            isinstance(t2, mwparserfromhell.parser.tokens.Text) and
            any(t in t2.text.lower() for t in _lowercase_cn_templates))
    try:
        return mwparserfromhell.parser.Builder().build(reduced_tokens)
    except mwparserfromhell.parser.ParserError:
        return None