docstr: return data that meets the minimum requirements of tsdata.
docstr_tok: ["return","data","that","meets","the","minimum","requirements","of","tsdata","."]
code: def preprocess_uci_electricity(self):
      """
      return data that meets the minimum requirements of tsdata.
      """
      if not os.path.exists(self.final_file_path):
          zip_file = zipfile.ZipFile(
              os.path.join(
                  os.path.expanduser(self.dir_path),
                  DATASET_NAME[self.name][0],
              )
          )
          zip_file.extractall(
              os.path.join(os.path.expanduser(self.dir_path))
          )
          download_file = os.path.join(
              self.dir_path, DATASET_NAME[self.name][0].split(".")[0]
          )
          os.rename(download_file + ".txt", self.final_file_path)
      df = pd.read_csv(
          self.final_file_path,
          delimiter=";",
          parse_dates=["Unnamed: 0"],
          low_memory=False,
      )
      self.df = pd.melt(
          df, id_vars=["Unnamed: 0"], value_vars=df.T.index[1:]
      ).rename(columns={"Unnamed: 0": "timestamp", "variable": "id"})
      self.df.value = self.df.value.apply(
          lambda x: str(x).replace(",", "")
      ).astype(np.float32)
      return self
  
imports: import os
  import re
  import zipfile
  import tarfile
  import requests
  import logging
  import pandas
  import numpy
  from bigdl.chronos.data.tsdataset import TSDataset
  from bigdl.nano.utils.common import invalidInputError
label_desc: Use image node_id 7 for calling the PublicDataset obj's underlying member method code with example usage: obj.preprocess_uci_electricity() and returns: self