class_docstr: A manager for parallel execution of jobs.
  
  A job must be of type :class:`Job` which produces a :class:`Result`
  object upon successful completion. The scheduler maintains a job and
  result queues.
  
  Notes:
      This class should be used as a context manager.
docstr: Enter the context manager.
docstr_tok: ["Enter","the","context","manager","."]
code: def __enter__(self):
      """Enter the context manager."""
      return self
  
file_path: hypertunity/hypertunity/scheduling/scheduler.py
imports: import multiprocessing
  import time
  from typing import List
  import joblib
  from hypertunity import utils
  from .jobs import Job, Result
label_desc: Use image node_id 3 for calling the Scheduler obj's underlying member method code with example usage: obj.__enter__() and returns: self