code: def test_append_many(self, sort, float_frame):
      chunks = [
          float_frame[:5],
          float_frame[5:10],
          float_frame[10:15],
          float_frame[15:],
      ]
  
      result = chunks[0]._append(chunks[1:])
      tm.assert_frame_equal(result, float_frame)
  
      chunks[-1] = chunks[-1].copy()
      chunks[-1]["foo"] = "bar"
      result = chunks[0]._append(chunks[1:], sort=sort)
      tm.assert_frame_equal(
          result.loc[:, float_frame.columns], float_frame
      )
      assert (result["foo"][15:] == "bar").all()
      assert result["foo"][:15].isna().all()
  
imports: import datetime
  from itertools import combinations
  import dateutil
  import numpy
  import pytest
  import pandas
  from pandas import DataFrame, Index, Series, Timestamp, concat, isna
  import pandas._testing
label_desc: Use image node_id 9 for calling the TestAppend obj's underlying member method code with example usage: obj.test_append_many(sort, float_frame) without return types