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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 add_instance_groups(self, jobflow_id, instance_groups):
 """ Adds instance groups to a running cluster. :type jobflow_id: str :param jobflow_id: The id of the jobflow which will take the new instance groups :type instance_groups: list(boto.emr.InstanceGroup) :param instance_groups: A list of instance groups to add to the job """

        if type(instance_groups) != types.ListType:
            instance_groups = [instance_groups]
        params = {}
        params['JobFlowId'] = jobflow_id
        params.update(self._build_instance_group_list_args(instance_groups))

        return self.get_object('AddInstanceGroups', params,
                               AddInstanceGroupsResponse, verb='POST')