code: def test_backend_config_set_backend_pattern_config(self):
      conf = BackendConfig("name1")
      self.assertEqual(len(conf.configs), 0)
      backend_op_config1 = self._get_backend_op_config1()
      backend_op_config2 = self._get_backend_op_config2()
      conf.set_backend_pattern_config(backend_op_config1)
      self.assertEqual(
          conf._pattern_complex_format_to_config,
          {
              (torch.nn.ReLU, torch.nn.Linear): backend_op_config1,
          },
      )
      conf.set_backend_pattern_config(backend_op_config2)
      self.assertEqual(
          conf._pattern_complex_format_to_config,
          {
              (torch.nn.ReLU, torch.nn.Linear): backend_op_config1,
              torch.add: backend_op_config2,
          },
      )
  
imports: import torch
  import torch.ao.nn.intrinsic
  import torch.ao.nn.qat
  import torch.ao.nn.quantized.reference
  from torch.testing._internal.common_quantization import QuantizationTestCase
  from torch.ao.quantization.backend_config import BackendConfig, BackendPatternConfig, DTypeConfig, DTypeWithConstraints, ObservationType
  from torch.ao.quantization.fuser_method_mappings import _sequential_wrapper2
  from torch.ao.quantization.fx.quantize_handler import _default_root_node_getter
label_desc: Use image node_id 22 for calling the TestBackendConfig obj's underlying member method code with example usage: obj.test_backend_config_set_backend_pattern_config() without return types