code: def config_get(key=None):
      """Print config key, or the whole config."""
      if key in (None, ""):
          click.echo(
              click.style(
                  """Config key not specified. Are you looking for "dask config list"?"""
              ),
              err=True,
          )
          exit(1)
      else:
          try:
              data = reduce(
                  lambda d, k: d[k], key.split("."), dask.config.config
              )
              if isinstance(data, (list, dict)):
                  click.echo_via_pager(dump(data))
              else:
                  click.echo(data)
          except KeyError:
              click.echo(
                  click.style(f"Section not found: {key}", fg="red"),
                  err=True,
              )
              exit(1)
  
file_path: dask/dask/cli.py
imports: from __future__ import annotations
  import warnings
  from functools import reduce
  import click
  import importlib_metadata
  from yaml import dump
  import dask
  from dask import __version__
label_desc: Use image node_id 6 for calling a global function with example usage: config_get(key) without return types