class_docstr: ArtifactExtractor class will extract artifacts from "streamalert_normalization" field in the
  records. The extracted artfiacts will be saved in the S3 bucket via a dedicated Firehose
  delivery stream and searchable from "artifacts" table in Athena.
code: def __init__(self, artifacts_fh_stream_name):
      self._dst_firehose_stream_name = artifacts_fh_stream_name
      self._artifacts = list()
  
      ArtifactExtractor._config = (
          ArtifactExtractor._config or config.load_config(validate=True)
      )
  
      ArtifactExtractor._firehose_client = (
          ArtifactExtractor._firehose_client
          or FirehoseClient.get_client(
              prefix=self.config["global"]["account"]["prefix"],
              artifact_extractor_config=self.config["global"]
              .get("infrastructure", {})
              .get("artifact_extractor", {}),
          )
      )
  
file_path: streamalert/streamalert/shared/artifact_extractor.py
imports: import re
  import uuid
  from streamalert.shared.firehose import FirehoseClient
  from streamalert.shared import CLASSIFIER_FUNCTION_NAME, config
  from streamalert.shared.metrics import MetricLogger
  from streamalert.shared.normalize import Normalizer, CONST_ARTIFACTS_FLAG
  from streamalert.shared.logger import get_logger
label_desc: Use image node_id 1 to create a new ArtifactExtractor object  with example: obj = ArtifactExtractor(artifacts_fh_stream_name)