code: def test_round_dst_border_ambiguous(self, method, unit):
      # GH 18946 round near "fall back" DST
      ts = Timestamp("2017-10-29 00:00:00", tz="UTC").tz_convert(
          "Europe/Madrid"
      )
      ts = ts.as_unit(unit)
      #
      result = getattr(ts, method)("h", ambiguous=True)
      assert result == ts
      assert (
          result._creso
          == getattr(NpyDatetimeUnit, f"NPY_FR_{unit}").value
      )
  
      result = getattr(ts, method)("h", ambiguous=False)
      expected = Timestamp("2017-10-29 01:00:00", tz="UTC").tz_convert(
          "Europe/Madrid"
      )
      assert result == expected
      assert (
          result._creso
          == getattr(NpyDatetimeUnit, f"NPY_FR_{unit}").value
      )
  
      result = getattr(ts, method)("h", ambiguous="NaT")
      assert result is NaT
  
      msg = "Cannot infer dst time"
      with pytest.raises(pytz.AmbiguousTimeError, match=msg):
          getattr(ts, method)("h", ambiguous="raise")
  
imports: from hypothesis import given, strategies
  import numpy
  import pytest
  import pytz
  from pandas._libs import lib
  from pandas._libs.tslibs import NaT, OutOfBoundsDatetime, Timedelta, Timestamp, iNaT, to_offset
  from pandas._libs.tslibs.dtypes import NpyDatetimeUnit
  from pandas._libs.tslibs.period import INVALID_FREQ_ERR_MSG
  import pandas._testing
label_desc: Use image node_id 12 for calling the TestTimestampRound obj's underlying member method code with example usage: obj.test_round_dst_border_ambiguous(method, unit) without return types