code: def _path(self, opt):
      build(opt)
  
      dt = opt["datatype"].split(":")[0]
      # Using matched set as valid and mismatched set as test
      if dt == "valid":
          dt = "dev"
      fname = dt + "_binary_sent.csv"
      path = os.path.join(opt["datapath"], "SST", fname)
  
      return path
  
file_path: ParlAI/parlai/tasks/sst/agents.py
imports: from parlai.core.teachers import DialogTeacher
  from parlai.utils.io import PathManager
  from .build import build
  import os
label_desc: Use image node_id 2 for calling the SSTTeacher obj's underlying member method code with example usage: obj._path(opt) and returns: path