code: def get_active_backend():
      """Return the active default backend"""
      active_backend_and_jobs = getattr(
          _backend, "backend_and_jobs", None
      )
      if active_backend_and_jobs is not None:
          return active_backend_and_jobs
      # We are outside of the scope of any parallel_backend context manager,
      # create the default backend instance now
      active_backend = BACKENDS[DEFAULT_BACKEND]()
      return active_backend, DEFAULT_N_JOBS
  
imports: from __future__ import division
  import os
  import sys
  from math import sqrt
  import functools
  import time
  import threading
  import itertools
  from numbers import Integral
  from contextlib import contextmanager
  import warnings
  from ...config import get_start_method
  from ._multiprocessing_helpers import mp
  from .format_stack import format_outer_frames
  from .logger import Logger, short_format_time
  from .my_exceptions import TransportableException, _mk_exception
  from .disk import memstr_to_bytes
  from ._parallel_backends import FallbackToBackend, MultiprocessingBackend, ThreadingBackend, SequentialBackend
  from ._compat import _basestring
  from ._parallel_backends import AutoBatchingMixin
  from ._parallel_backends import ParallelBackendBase
label_desc: Use image node_id 1 for calling a global function with example usage: get_active_backend() and returns: active_backend,  DEFAULT_N_JOBS, active_backend_and_jobs