class_docstr: Dataset with Data(H)andler
  
  User should try to put the data preprocessing functions into handler.
  Only following data processing functions should be placed in Dataset:
  
  - The processing is related to specific model.
  
  - The processing is related to data split.
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docstr: Give a query, retrieve the according data
  
  Parameters
  ----------
  slc : please refer to the docs of `prepare`
          NOTE: it may not be an instance of slice. It may be a segment of `segments` from `def prepare`
docstr_tok: ["Give","a","query",",","retrieve","the","according","data","Parameters","--","--","--","--","--","slc",":","please","refer","to","the","docs","of","`","prepare","`","NOTE",":","it","may","not","be","an","instance","of","slice",".","It","may","be","a","segment","of","`","segments","`","from","`","def","prepare","`"]
code: def _prepare_seg(self, slc, **kwargs):
      """
      Give a query, retrieve the according data
  
      Parameters
      ----------
      slc : please refer to the docs of `prepare`
              NOTE: it may not be an instance of slice. It may be a segment of `segments` from `def prepare`
      """
      if hasattr(self, "fetch_kwargs"):
          return self.handler.fetch(slc, **kwargs, **self.fetch_kwargs)
      else:
          return self.handler.fetch(slc, **kwargs)
  
imports: from ...utils.serial import Serializable
  from typing import Callable, Union, List, Tuple, Dict, Text, Optional
  from ...utils import init_instance_by_config, np_ffill, time_to_slc_point
  from ...log import get_module_logger
  from .handler import DataHandler, DataHandlerLP
  from copy import copy, deepcopy
  from inspect import getfullargspec
  import pandas
  import numpy
  import bisect
  from ...utils import lazy_sort_index
  from .utils import get_level_index
label_desc: Use image node_id 5 for calling the DatasetH obj's underlying member method code with example usage: obj._prepare_seg(slc) and returns: self, self