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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 unauthorized(self, response):
        '''Override to change the WWW-Authenticate challenge'''
        realm = current_app.config.get('HTTP_OAUTH_REALM', 'uData')
        challenge = 'Bearer realm="{0}"'.format(realm)

        response.headers['WWW-Authenticate'] = challenge
        return response