[Python] Slicing netCDF4 dataset based on specific time interval using xarray

I have a netCDF4 dataset for the following datatime which is stored in _date_times variable:-

<xarray.DataArray 'Time' (Time: 21)> Size: 168B
array(['2025-01-30T00:00:00.000000000', '2025-01-30T06:00:00.000000000',
'2025-01-30T12:00:00.000000000', '2025-01-30T18:00:00.000000000',
'2025-01-31T00:00:00.000000000', '2025-01-31T06:00:00.000000000',
'2025-01-31T12:00:00.000000000', '2025-01-31T18:00:00.000000000',
'2025-02-01T00:00:00.000000000', '2025-02-01T06:00:00.000000000',
'2025-02-01T12:00:00.000000000', '2025-02-01T18:00:00.000000000',
'2025-02-02T00:00:00.000000000', '2025-02-02T06:00:00.000000000',
'2025-02-02T12:00:00.000000000', '2025-02-02T18:00:00.000000000',
'2025-02-03T00:00:00.000000000', '2025-02-03T06:00:00.000000000',
'2025-02-03T12:00:00.000000000', '2025-02-03T18:00:00.000000000',
'2025-02-04T00:00:00.000000000'], dtype='datetime64[ns]')


The above data is of six hour interval. However, I need to convert the dataset to twelve hourly dataset. The filtered dataset should look like this:-

<xarray.DataArray 'Time' (Time: 21)> Size: 168B
array(['2025-01-30T00:00:00.000000000', '2025-01-30T12:00:00.000000000',
'2025-01-31T00:00:00.000000000', '2025-01-31T12:00:00.000000000',
'2025-02-01T00:00:00.000000000', '2025-02-01T12:00:00.000000000',
'2025-02-02T00:00:00.000000000', '2025-02-02T12:00:00.000000000',
'2025-02-03T00:00:00.000000000', '2025-02-03T12:00:00.000000000',
'2025-02-04T00:00:00.000000000'], dtype='datetime64[ns]')


What I tried was:-

xr_ds.sel(Time=slice(_date_times[0], _date_times[-1]), freq='12 h')



Off course, it won't work as there is no option to specify freq.

How do I slice dataset containing only on specific time interval?

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