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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def handle_not_allowed(environ, start_response):
 """Return a 405 response when method is not allowed. If _methods are in routing_args, send an allow header listing the methods that are possible on the provided URL. """

    _methods = util.wsgi_path_item(environ, '_methods')
    headers = {}
    if _methods:
        headers['allow'] = str(_methods)
    raise webob.exc.HTTPMethodNotAllowed(
        ('The method specified is not allowed for this resource.'),
        headers=headers, json_formatter=util.json_error_formatter)