code: def db_continue( block_id, consensus_hash ):
      
  
      # every so often, clean up
      if (block_id % 20) == 0:
          log.debug("Pre-emptive garbage collection at %s" % block_id)
          gc.collect(2)
  
      return is_running() or os.environ.get("BLOCKSTACK_TEST") == "1"
docs: (required by virtualchain state engine)
  
      Called when virtualchain has synchronized all state for this block.
      Blockstack uses this as a preemption point where it can safely
      exit if the user has so requested.