code: def dec(self, metric_name, value=1, echo=False):
      return self.inc(metric_name, -value, echo)
  
file_path: ray/python/ray/experimental/raysort/tracing_utils.py
imports: import datetime
  import functools
  import logging
  import time
  from typing import List, Tuple
  import ray
  from ray.experimental.raysort import constants, logging_utils
  from ray.util.metrics import Gauge, Histogram
label_desc: Use image node_id 4 for calling the ProgressTracker obj's underlying member method code with example usage: obj.dec(metric_name, value, echo) and returns: self