code: def _workers(workers):
      if workers is None:
          return getattr(_config, "default_workers", 1)
  
      if workers < 0:
          if workers >= -_cpu_count:
              workers += 1 + _cpu_count
          else:
              raise ValueError(
                  f"workers value out of range; got {workers}, must not be"
                  f" less than {-_cpu_count}"
              )
      elif workers == 0:
          raise ValueError("workers must not be zero")
  
      return workers
  
file_path: scipy/scipy/fft/_pocketfft/helper.py
imports: from numbers import Number
  import operator
  import os
  import threading
  import contextlib
  import numpy
  from .pypocketfft import good_size
label_desc: Use image node_id 8 for calling a global function with example usage: _workers(workers) and returns: workers, getattr