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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 scale(self, replicas):
 """ Scale service container. Args: replicas (int):
 The number of containers that should be running. Returns: bool: ``True`` if successful. """


        if 'Global' in self.attrs['Spec']['Mode'].keys():
            raise InvalidArgument('Cannot scale a global container')

        service_mode = ServiceMode('replicated', replicas)
        return self.client.api.update_service(self.id, self.version,
                                              mode=service_mode,
                                              fetch_current_spec=True)