code: def test_add_all(self):
      conf = Configuration()
      conf.set_string("k1", "v1")
      conf2 = Configuration()
  
      conf2.add_all(conf)
      value1 = conf2.get_string("k1", "")
  
      self.assertEqual(value1, "v1")
  
      conf2.add_all(conf, "conf_")
      value2 = conf2.get_string("conf_k1", "")
  
      self.assertEqual(value2, "v1")
  
file_path: flink/flink-python/pyflink/common/tests/test_configuration.py
imports: from copy import deepcopy
  from pyflink.common import Configuration
  from pyflink.testing.test_case_utils import PyFlinkTestCase
label_desc: Use image node_id 5 for calling the ConfigurationTests obj's underlying member method code with example usage: obj.test_add_all() without return types