class_docstr: Driver for Importer.
code: def pre_execution(
      self,
      input_dict: Dict[str, types.BaseChannel],
      output_dict: Dict[str, types.Channel],
      exec_properties: Dict[str, Any],
      driver_args: data_types.DriverArgs,
      pipeline_info: data_types.PipelineInfo,
      component_info: data_types.ComponentInfo,
  ) -> data_types.ExecutionDecision:
      # Registers contexts and execution.
      contexts = self._metadata_handle.register_pipeline_contexts_if_not_exists(
          pipeline_info
      )
      execution = self._metadata_handle.register_execution(
          exec_properties=exec_properties,
          pipeline_info=pipeline_info,
          component_info=component_info,
          contexts=contexts,
      )
      # Create imported artifacts.
      output_key = exec_properties[OUTPUT_KEY_KEY]
      output_channel = output_dict[output_key]
      output_artifacts = generate_output_dict(
          self._metadata_handle,
          uri=exec_properties[SOURCE_URI_KEY],
          properties=output_channel.additional_properties,
          custom_properties=output_channel.additional_custom_properties,
          reimport=exec_properties[REIMPORT_OPTION_KEY],
          output_artifact_class=output_channel.type,
          output_key=output_key,
      )
  
      # Update execution with imported artifacts.
      self._metadata_handle.update_execution(
          execution=execution,
          component_info=component_info,
          output_artifacts=output_artifacts,
          execution_state=metadata.EXECUTION_STATE_CACHED,
          contexts=contexts,
      )
  
      output_dict[output_key] = channel_utils.as_channel(
          output_artifacts[output_key]
      )
  
      return data_types.ExecutionDecision(
          input_dict={},
          output_dict=output_artifacts,
          exec_properties=exec_properties,
          execution_id=execution.id,
          use_cached_results=False,
      )
  
imports: from typing import Any, Dict, List, Optional, Type, Union
  import absl
  from tfx import types
  from tfx.dsl.components.base import base_driver
  from tfx.dsl.components.base import base_node
  from tfx.orchestration import data_types
  from tfx.orchestration import metadata
  from tfx.types import channel_utils
  from tfx.utils import doc_controls
  from ml_metadata import errors
  from ml_metadata.proto import metadata_store_pb2
label_desc: Use image node_id 1 for calling the ImporterDriver obj's underlying member method code with example usage: obj.pre_execution(input_dict, output_dict, exec_properties, driver_args, pipeline_info, component_info) and returns: data_types