code: def _getdata(self, dataname, **kwargs):
      maincode = dataname[0:2]
      subcode = dataname[2:6]
  
      datapath = os.path.join(
          self.p.basepath,
          "RealServer",
          "Data",
          maincode,
          subcode,  # 01 00XX
          dataname,
      )
  
      newkwargs = self.p._getkwargs()
      newkwargs.update(kwargs)
      kwargs["dataname"] = datapath
      return self.DataCls(**kwargs)
  
file_path: backtrader/backtrader/feeds/vchart.py
imports: from __future__ import absolute_import, division, print_function, unicode_literals
  import datetime
  import struct
  import os.path
  from ..None import feed
  from ..None import TimeFrame
  from ..utils import date2num
label_desc: Use image node_id 1 for calling the VChartFeed obj's underlying member method code with example usage: obj._getdata(dataname) and returns: self