class_docstr: Desc: Data preprocessing,
code: def __init__(self, filename, capacity=134, day_len=24 * 6):
      super().__init__()
      self.unit_size = day_len
  
      self.start_col = 0
      self.capacity = capacity
      self.filename = filename
  
      self.__read_data__()
  
imports: import os
  import time
  import datetime
  import numpy
  import pandas
  import paddle
  from paddle.io import Dataset
  import pgl
  from pgl.utils.logger import log
label_desc: Use image node_id 1 to create a new TestPGL4WPFDataset object from inherited base classes: Dataset with example: obj = TestPGL4WPFDataset(filename, capacity, day_len)