• PyPI：https://pypi.org/project/Werkzeug/
• 文档：https://werkzeug.palletsprojects.com/en/latest/
• 代码：https://github.com/pallets/werkzeug/

示例

from werkzeug.wrappers import Request, Response
from werkzeug.routing import Map, Rule

class Application:
    def __init__(self):
        self.url_map = Map([
            Rule('/', endpoint='hello')
        ])

    def hello(self, request):
        text = 'Hello, World!'
        response = Response(text, content_type='text/plain')
        return response

    @Request.application
    def __call__(self, request):
        adapter = self.url_map.bind_to_environ(request.environ)
        endpoint, values = adapter.match()

        handler = getattr(self, endpoint)
        return handler(request, **values)

if __name__ == '__main__':
    from werkzeug.serving import run_simple
    app = Application()
    run_simple('localhost', 5000, app)

Werkzeug 与协程（async/await）

Werkzeug 1.x 开始已经提供了对协程的支持。
PS：WSGI 规范是基于同步的设计，没有较好的适配异步编程，所以后面一些更年轻的框架选择了 ASGI（Async Server Gateway Interface）。
PS：2014/03/01, WSGI
PS：2021/11/06, 体验 ASGI

import asyncio
from werkzeug.wrappers import Request, Response
from werkzeug.routing import Map, Rule

class Application:
    def __init__(self):
        self.url_map = Map([
            Rule('/', endpoint='hello')
        ])

    async def hello(self, request):
        text = 'Hello, World!'
        response = Response(text, content_type='text/plain')
        return response

    @Request.application
    async def __call__(self, request):
        adapter = self.url_map.bind_to_environ(request.environ)
        endpoint, values = adapter.match()

        handler = getattr(self, endpoint)
        response = await handler(request, **values)
        return response

if __name__ == '__main__':
    from werkzeug.serving import run_simple
    app = Application()
    run_simple('localhost', 5000, app)

附：版本历史