code: def _null_backend_context(dummy_backend):
      """
      A dummy context manager that does nothing, equivalent to
      `contextlib.nullcontext` (which isn't implemented in Python<3.7).
      Used in `manage_backend` when the decorated call to `hypertools.plot`
      happens inside the `hypertools.set_interactive_backend` context.
  
      Parameters
      ----------
      dummy_backend : object
          Arbitrary value that is never used, but is required to make this
          function syntactically match `hypertools.set_interactive_backend`
      """
      yield
  
imports: import inspect
  import sys
  import traceback
  import warnings
  from contextlib import contextmanager, redirect_stdout
  from functools import wraps
  from io import StringIO
  from os import getenv
  from typing import Iterable
  import matplotlib
  import matplotlib.pyplot
  from .._shared.exceptions import HypertoolsBackendError
label_desc: Use image node_id 7 for calling a global function with example usage: _null_backend_context(dummy_backend) without return types