code: def test_datetimetz_dtype_match():
      dtype = DatetimeTZDtype(unit="ns", tz="US/Eastern")
      assert (
          find_common_type([dtype, dtype])
          == "datetime64[ns, US/Eastern]"
      )
  
file_path: pandas/pandas/tests/dtypes/cast/test_find_common_type.py
imports: import numpy
  import pytest
  from pandas.core.dtypes.cast import find_common_type
  from pandas.core.dtypes.common import pandas_dtype
  from pandas.core.dtypes.dtypes import CategoricalDtype, DatetimeTZDtype, IntervalDtype, PeriodDtype
  from pandas import Categorical, Index
label_desc: Use image node_id 4 for calling a global function with example usage: test_datetimetz_dtype_match() without return types