code: def create_machine_group(self, project_name, group_detail):
          
  
          headers = {}
          params = {}
          resource = "/machinegroups"
          headers['Content-Type'] = 'application/json'
          body = six.b(json.dumps(group_detail.to_json()))
          headers['x-log-bodyrawsize'] = str(len(body))
          (resp, headers) = self._send("POST", project_name, body, resource, params, headers)
          return CreateMachineGroupResponse(headers, resp)
docs: create machine group in a project
          Unsuccessful opertaion will cause an LogException.
  
          :type project_name: string
          :param project_name: the Project name 
  
          :type group_detail: MachineGroupDetail
          :param group_detail: the machine group detail config
  
          :return: CreateMachineGroupResponse
          
          :raise: LogException