'Regression test for https://github.com/astropy/astropy/issues/2463
Only test against `StringIO.StringIO` on Python versions that have it.
Note: `io.StringIO` is not supported for this purpose as it does not
accept a bytes stream.'

@pytest.mark.skipif('not    HAVE_STRINGIO')
def test_write_stringio(self):

    self._test_write_string_bytes_io(StringIO.StringIO())
