code: def test_concat_empty_series_dtypes_triple(self):
      assert (
          concat(
              [
                  Series(dtype="M8[ns]"),
                  Series(dtype=np.bool_),
                  Series(dtype=np.int64),
              ]
          ).dtype
          == np.object_
      )
  
imports: import numpy
  import pytest
  import pandas
  from pandas import DataFrame, RangeIndex, Series, concat, date_range
  import pandas._testing
label_desc: Use image node_id 7 for calling the TestEmptyConcat obj's underlying member method code with example usage: obj.test_concat_empty_series_dtypes_triple() without return types