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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 handler(self, environ, start_response):
 """XMLRPC service for windmill browser core to communicate with"""


        if environ['REQUEST_METHOD'] == 'POST':
            return self.handle_POST(environ, start_response)
        else:
            start_response("400 Bad request", [('Content-Type', 'text/plain')])
            return ['']