code: def _validateTrace(self, chrome_trace_format):
      # Check that the supplied string is valid JSON.
      trace = json.loads(chrome_trace_format)
      # It should have a top-level key containing events.
      self.assertTrue("traceEvents" in trace)
      # Every event in the list should have a 'ph' field.
      for event in trace["traceEvents"]:
          self.assertTrue("ph" in event)
  
file_path: tensorflow-upstream/tensorflow/python/client/timeline_test.py
imports: import json
  from tensorflow.core.protobuf import config_pb2
  from tensorflow.python.client import session
  from tensorflow.python.client import timeline
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import test_util
  from tensorflow.python.framework import ops
  from tensorflow.python.ops import math_ops
  from tensorflow.python.ops import variables
  from tensorflow.python.platform import test
label_desc: Use image node_id 1 for calling the TimelineTest obj's underlying member method code with example usage: obj._validateTrace(chrome_trace_format) without return types