code: def get_result_str(self):
      return " ".join(
          metric.get_result_str() for metric in self.metrics
      )
  
imports: import os
  import time
  import hashlib
  import numpy
  import tensorflow
  import dnnlib
  import dnnlib.tflib
  from training import misc
  from training import dataset
label_desc: Use image node_id 3 for calling the MetricGroup obj's underlying member method code with example usage: obj.get_result_str() and returns: str