n_jobs = max(1, cpu_count() + n_jobs + 1)
// use the cached optimizer for particular parameter space
key = str(param_space)
if key not in self.optimizer_:
self.optimizer_[key] = self._make_optimizer(param_space)
optimizer = self.optimizer_[key]
After Change
// use the cached optimizer for particular parameter space
if space_id not in self.search_spaces_:
raise ValueError("Unknown space %s" % space_id)
// get the search space for a step
search_space = self.search_spaces_[space_id]
if isinstance(search_space, tuple):