Task scheduler with queue and scheduling (by time)?

Question

linux

Tell me a task scheduler with the ability to add to the queue and schedule (by time)? Under Linux, preferably extremely simple... Native or Python.
It is necessary that he be able to give commands:

• run the specified command at the same time in the specified queue,
  
• run the specified command continuously in the specified queue,
  
• schedule to run the specified command at the specified time (ala Cron) in the specified queue,
  
• stop running the specified command on the specified queue.
  

UPD.
The queues are synchronous.
When setting several "permanent" tasks, their totality is constantly performed, and not each of them.

Answer 1

Cron\at\Anacron\