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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 basicauthfail(self, realm = b'all'):
 """ Return 401 for authentication failure. This will end the handler. """

        if not isinstance(realm, bytes):
            realm = realm.encode('ascii')
        self.start_response(401, [(b'WWW-Authenticate', b'Basic realm="' + realm + b'"')])
        self.exit(b'<h1>' + _createstatus(401) + b'</h1>')