code: def on_predict_batch_begin(self, batch, logs=None):
      if batch == self.start_batch:
          self.state["benchmark_begin"] = time.time()
  
imports: import time
  import numpy
  import tensorflow
  from absl import flags
  import keras
label_desc: Use image node_id 4 for calling the BenchmarkMetricsCallback obj's underlying member method code with example usage: obj.on_predict_batch_begin(batch, logs) without return types