code: def test_to_dict(self):
      metrics = [RMSE(), MSE(), MAE(), R2Score()]
      predict = np.random.random_sample(1000) * 10
      label = np.random.random_sample(1000) * 10
      for m in metrics:
          print(m(predict, label).to_dict())
  
file_path: FATE/python/fate/ml/evaluation/test/test_reg_metric.py
imports: import unittest
  import numpy
  from sklearn.metrics import mean_squared_error, mean_absolute_error, r2_score
  from fate.ml.evaluation.regression import *
label_desc: Use image node_id 5 for calling the TestMetric obj's underlying member method code with example usage: obj.test_to_dict() without return types