code: def test_no_exist_data(self):
      fields = ["P($$roewa_q)", "P($$yoyni_q)", "$close"]
      data = D.features(
          ["sh600519", "sh601988"],
          fields,
          start_time="2019-01-01",
          end_time="2019-07-19",
          freq="day",
      )
      data[
          "$close"
      ] = 1  # in case of different dataset gives different values
      expect = """
                                 P($$roewa_q)  P($$yoyni_q)  $close
          instrument datetime
          sh600519   2019-01-02       0.25522      0.243892       1
                     2019-01-03       0.25522      0.243892       1
                     2019-01-04       0.25522      0.243892       1
                     2019-01-07       0.25522      0.243892       1
                     2019-01-08       0.25522      0.243892       1
          ...                             ...           ...     ...
          sh601988   2019-07-15           NaN           NaN       1
                     2019-07-16           NaN           NaN       1
                     2019-07-17           NaN           NaN       1
                     2019-07-18           NaN           NaN       1
                     2019-07-19           NaN           NaN       1
  
          [266 rows x 3 columns]
          """
      self.check_same(data, expect)
  
imports: import sys
  import qlib
  import shutil
  import unittest
  import pytest
  import pandas
  import baostock
  from pathlib import Path
  from qlib.data import D
  from qlib.tests.data import GetData
  from dump_pit import DumpPitData
  from collector import Run
label_desc: Use image node_id 7 for calling the TestPIT obj's underlying member method code with example usage: obj.test_no_exist_data() without return types