code: def init_chain_adapters(
      *,
      backend: mcb.Backend,
      chains: int,
      initial_point: Mapping[str, np.ndarray],
      step: Union[CompoundStep, BlockedStep],
      model: Model,
  ) -> Tuple[mcb.Run, List[ChainRecordAdapter]]:
      """Create an McBackend metadata description for the MCMC run.
  
      Parameters
      ----------
      backend
          An McBackend `Backend` instance.
      chains
          Number of chains to initialize.
      initial_point
          Dictionary mapping value variable names to initial values.
      step : CompoundStep or BlockedStep
          The step method that iterates the MCMC.
      model : pm.Model
          The current PyMC model.
  
      Returns
      -------
      adapters
          Chain recording adapters that wrap McBackend Chains in the PyMC IBaseTrace interface.
      """
      meta, point_fn = make_runmeta_and_point_fn(
          initial_point=initial_point, step=step, model=model
      )
      run = backend.init_run(meta)
      statsbj = StatsBijection(step.stats_dtypes)
      adapters = [
          ChainRecordAdapter(
              chain=run.init_chain(chain_number=chain_number),
              point_fn=point_fn,
              stats_bijection=statsbj,
          )
          for chain_number in range(chains)
      ]
      return run, adapters
  
imports: import base64
  import logging
  import pickle
  from typing import Any, Dict, List, Mapping, Optional, Sequence, Tuple, Union, cast
  import hagelkorn
  import mcbackend
  import numpy
  from mcbackend.npproto.utils import ndarray_from_numpy
  from pytensor.compile.sharedvalue import SharedVariable
  from pytensor.graph.basic import Constant
  from pymc.backends.base import IBaseTrace
  from pymc.model import Model
  from pymc.pytensorf import PointFunc
  from pymc.step_methods.compound import BlockedStep, CompoundStep, StatsBijection, check_step_emits_tune, flat_statname, flatten_steps
label_desc: Use image node_id 4 for calling a global function with example usage: init_chain_adapters() and returns: run,  adapters