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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 SensorMetatagsPost(self, sensor_id, metatags, namespace = None):

 """
 Attach metatags to a sensor for a specific namespace
 
 @param sensor_id (int) - Id of the sensor to attach metatags to
 @param namespace (string) - Namespace for which to attach metatags
 @param metatags (dictionary) - Metatags to attach to the sensor
 
 @return (bool) - Boolean indicating whether SensorMetatagsPost was successful
 """

        ns = "default" if namespace is None else namespace
        if self.__SenseApiCall__("/sensors/{0}/metatags.json?namespace={1}".format(sensor_id, ns), "POST", parameters = metatags):
            return True
        else:
            self.__error__ = "api call unsuccessful"
            return False