code: def build_managers(app, conf):
      
      # Load default options from config file that apply to all
      # managers.
      default_options = _get_default_options(conf)
  
      manager_descriptions = ManagerDescriptions()
      if "job_managers_config" in conf:
          job_managers_config = conf.get("job_managers_config", None)
          _populate_manager_descriptions_from_ini(manager_descriptions, job_managers_config)
      elif "managers" in conf:
          for manager_name, manager_options in conf["managers"].items():
              manager_description = ManagerDescription.from_dict(manager_options, manager_name)
              manager_descriptions.add(manager_description)
      elif "manager" in conf:
          manager_description = ManagerDescription.from_dict(conf["manager"])
          manager_descriptions.add(manager_description)
      else:
          manager_descriptions.add(ManagerDescription())
  
      manager_classes = _get_managers_dict()
      managers = {}
      for manager_name, manager_description in manager_descriptions.descriptions.items():
          manager_options = dict(default_options)
          manager_options.update(manager_description.manager_options)
  
          manager_class = manager_classes[manager_description.manager_type]
          manager = _build_manager(manager_class, app, manager_name, manager_options)
          managers[manager_name] = manager
  
      return managers
docs: Takes in a config file as outlined in job_managers.ini.sample and builds
      a dictionary of job manager objects from them.