code: def main():
      with core_v2.init_context(
          defaults=core_v2.DefaultConfig(
              name="unmanaged-context-manager",
          ),
      ) as core_context:
          for i in range(100):
              print(f"training loss: {random.random()}")
  
              core_context.train.report_training_metrics(
                  steps_completed=i, metrics={"loss": random.random()}
              )
  
              if (i + 1) % 10 == 0:
                  print(f"validation loss: {random.random()}")
  
                  core_context.train.report_validation_metrics(
                      steps_completed=i,
                      metrics={"loss": random.random()},
                  )
  
label_desc: Use image node_id 1 for calling a global function with example usage: main() without return types