docstr: Starts a new bracket based on Hyperband
code: def _start_new_bracket(self) -> SHBracketManager:
      """Starts a new bracket based on Hyperband"""
      # start new bracket
      self.iteration_counter += (
          1  # iteration counter gives the bracket count or bracket ID
      )
      n_configs, budgets = self.get_next_iteration(
          self.iteration_counter
      )
      bracket = SHBracketManager(
          n_configs=n_configs,
          budgets=budgets,
          bracket_id=self.iteration_counter,
          duplicates=self.duplicates,
      )
      self.active_brackets.append(bracket)
      return bracket
  
imports: from __future__ import annotations
  import logging
  from collections import defaultdict
  from copy import deepcopy
  from typing import ClassVar, NamedTuple
  import numpy
  from orion.algo.base import BaseAlgorithm
  from orion.algo.dehb.brackets import SHBracketManager
  from orion.algo.space import Fidelity, Space
  from orion.core.utils import format_trials
  from orion.core.utils.module_import import ImportOptional
  from orion.core.worker.trial import Trial
label_desc: Use image node_id 3 for calling the _CustomDEHBImpl obj's underlying member method code with example usage: obj._start_new_bracket() and returns: bracket