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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 _calculate_health(self):
 """Returns a string representation of the node health @returns: GREEN if fully connected, YELLOW if partially connected, RED if not connected """

        if self.redis_connected and self.kafka_connected:
            return "GREEN"
        elif self.redis_connected or self.kafka_connected:
            return "YELLOW"
        else:
            return "RED"