class_docstr: A monitor to collect statistic during tuning
class_docstr_tok: ["A","monitor","to","collect","statistic","during","tuning"]
docstr: get wall clock time stamp of all trials
docstr_tok: ["get","wall","clock","time","stamp","of","all","trials"]
code: def trial_timestamps(self):
      """get wall clock time stamp of all trials"""
      return np.array(self.timestamps)
  
file_path: tvm/python/tvm/autotvm/tuner/callback.py
imports: import sys
  import time
  import logging
  import numpy
  from ..None import record
  from ..utils import format_si_prefix
label_desc: Use image node_id 5 for calling the Monitor obj's underlying member method code with example usage: obj.trial_timestamps() and returns: np