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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 get_config(cls, service, config=None):
 """Get get configuration of the specified rate limiter :param str service: rate limiter name :param config: optional global rate limiters configuration. If not specified, then use rate limiters configuration specified at application level """

        config = config or cls.get_configs()
        return config[service]