docstr: Get the specific algorithm.
  :param str algorithm_name: name of the algorithm to use(file name).
  :return: algorithm object.
docstr_tok: ["Get","the","specific","algorithm",".",":","param","str","algorithm_name",":","name","of","the","algorithm","to","use","(","file","name",")",".",":","return",":","algorithm","object","."]
code: def _get_algorithm(self, algorithm_name):
      """
      Get the specific algorithm.
      :param str algorithm_name: name of the algorithm to use(file name).
      :return: algorithm object.
      """
      try:
          algorithm = anomaly_detector_algorithms[algorithm_name]
          return algorithm
      except KeyError:
          raise exceptions.AlgorithmNotFound(
              "luminol.AnomalyDetector: "
              + str(algorithm_name)
              + " not found."
          )
  
file_path: luminol/src/luminol/anomaly_detector.py
imports: from luminol import exceptions, utils
  from luminol.algorithms.anomaly_detector_algorithms.all import anomaly_detector_algorithms
  from luminol.modules.anomaly import Anomaly
  from luminol.modules.time_series import TimeSeries
  from luminol.constants import ANOMALY_DETECTOR_ALGORITHM, ANOMALY_THRESHOLD, ANOMALY_DETECTOR_REFINE_ALGORITHM, DEFAULT_SCORE_PERCENT_THRESHOLD
label_desc: Use image node_id 3 for calling the AnomalyDetector obj's underlying member method code with example usage: obj._get_algorithm(algorithm_name) and returns: algorithm