sqlalchemy:AttributeError:“tuple”对象没有属性“insert”

import logging

from pylons import request, response, session, tmpl_context as c
from pylons.controllers.util import abort, redirect_to

from myku.lib.base import BaseController, render
from sqlalchemy.sql import select
import meta
import myku.lib.helpers as h

log = logging.getLogger(__name__)

class IndexController(BaseController):
    def __init__(self):
        self.haiku_table = meta.haiku_table
        self.conn = meta.engine.connect()
        BaseController.__init__(self)

    def index(self, genre, title):
        ss = select([self.haiku_table], self.haiku_table.c.genre==str(genre).lower(),  self.haiku_table.c.title==str(title).lower())
       result = self.conn.execute(ss)
       return result

    def new_haiku(self):
       return render('/newku.html')

    def submit(self):
        title = request.params.get('title')
        haiku = request.params.get('haiku')
        genre = request.params.get('genre')
        author = request.params.get('author')
        form_dict = {'title': title, 'haiku': haiku, 'genre': genre, 'author': author}
        ins = self.haiku_table.insert(values=form_dict)
        result = self.conn.execute(ins)
        return res

from sqlalchemy.engine import create_engine
from sqlalchemy import schema, types

metadata = schema.MetaData()

haiku_table = ('haiku', metadata,
               schema.Column('title', types.Text(), primary_key=True),
               schema.Column('haiku', types.Text()),
               schema.Column('genre', types.Text()),
               schema.Column('author', types.Text())
               )

engine = create_engine('sqlite:///F:\\MyKu\\myku\\haiku')
metadata.bind = engine

metadata.create_all(checkfirst=True)

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