code: def test_astype_column_metadata(self, dtype):
      # GH#19920
      columns = Index([100, 200, 300], dtype=np.uint64, name="foo")
      df = DataFrame(np.arange(15).reshape(5, 3), columns=columns)
      df = df.astype(dtype)
      tm.assert_index_equal(df.columns, columns)
  
imports: import re
  import numpy
  import pytest
  import pandas.util._test_decorators
  import pandas
  from pandas import Categorical, CategoricalDtype, DataFrame, DatetimeTZDtype, Index, Interval, IntervalDtype, NaT, Series, Timedelta, Timestamp, concat, date_range, option_context
  import pandas._testing
label_desc: Use image node_id 18 for calling the TestAstype obj's underlying member method code with example usage: obj.test_astype_column_metadata(dtype) without return types