code: def __init__(
      self, folder_with_cropped_data, preprocessed_output_folder
  ):
      super(ExperimentPlanner2D_v21, self).__init__(
          folder_with_cropped_data, preprocessed_output_folder
      )
      self.data_identifier = "nnUNetData_plans_v2.1_2D"
      self.plans_fname = join_paths(
          self.preprocessed_output_folder,
          "nnUNetPlansv2.1_plans_2D.pkl",
      )
      self.unet_base_num_features = 32
      self.unet_max_num_filters = 512
      self.unet_max_numpool = 999
  
      self.preprocessor_name = PreprocessorFor2D
  
imports: import os
  import pickle
  import shutil
  from collections import OrderedDict
  from .image_crop import get_case_identifier_from_npz
  from .preprocessing import GenericPreprocessor, PreprocessorFor2D
  from .experiment_utils import *
  from .path_utils import join_paths
label_desc: Use image node_id 1 to create a new ExperimentPlanner2D_v21 object from inherited base classes: ExperimentPlanner with example: obj = ExperimentPlanner2D_v21(folder_with_cropped_data, preprocessed_output_folder)