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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 badRequestMethod(self, environ, start_response):
 """ Return HTTP 400 Bad Request. """

        response = "400 Bad Request\n\nTo access this PyAMF gateway you " \
            "must use POST requests (%s received)" % environ['REQUEST_METHOD']

        start_response('400 Bad Request', [
            ('Content-Type', 'text/plain'),
            ('Content-Length', str(len(response))),
            ('Server', gateway.SERVER_NAME),
        ])

        return [response]