Update wsgiref.rst (#10488)

Author: andresdelfino

Doc/library/wsgiref.rst

@@ -767,7 +767,7 @@ This is a working "Hello World" WSGI application::
    # use a function (note that you're not limited to a function, you can
    # use a class for example). The first argument passed to the function
    # is a dictionary containing CGI-style environment variables and the
-   # second variable is the callable object (see PEP 333).
+   # second variable is the callable object.
    def hello_world_app(environ, start_response):
        status = '200 OK'  # HTTP Status
        headers = [('Content-type', 'text/plain; charset=utf-8')]  # HTTP Headers