code: def start(self):
      self.raw_df = pd.read_csv(self.raw_data)
      self.next(self.split_data)
  
file_path: wandb/tests/functional_tests/t0_main/metaflow/wandb-example-flow-decoclass.py
imports: import os
  import pandas
  from metaflow import FlowSpec, Parameter, step
  from sklearn.ensemble import RandomForestClassifier
  from sklearn.metrics import accuracy_score
  from sklearn.model_selection import train_test_split
  from wandb.integration.metaflow import wandb_log
label_desc: Use image node_id 1 for calling the WandbExampleFlowDecoClass obj's underlying member method code with example usage: obj.start() without return types