code: def __init__(self, rule, checkpoints):
      self.rule = rule
      self.checkpoints = checkpoints
  
file_path: snakemake/snakemake/checkpoints.py
imports: from snakemake.common import async_run
  from snakemake.exceptions import IncompleteCheckpointException, WorkflowError
  from snakemake.io import checkpoint_target
label_desc: Use image node_id 1 to create a new Checkpoint object  with example: obj = Checkpoint(rule, checkpoints)