code: def set_cpus(self, cpus=0):
          
          from multiprocessing import cpu_count
  
          max_cpus = cpu_count()
          if not 0 < cpus < max_cpus:
              cpus = max_cpus
          self.add_option("--cpus", default=cpus, type="int",
                       help="Number of CPUs to use, 0=unlimited [default: %default]")
docs: Add --cpus options to specify how many threads to use.