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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def warm_night_frequency(tasmin, thresh='22 degC', freq='YS'):
 r"""Frequency of extreme warm nights Return the number of days with tasmin > thresh per period Parameters tasmin : xarray.DataArray Minimum daily temperature [℃] or [K] thresh : str Threshold temperature on which to base evaluation [℃] or [K]. Default : '22 degC' freq : str, optional Resampling frequency Returns ------- xarray.DataArray The number of days with tasmin > thresh per period """

    thresh = utils.convert_units_to(thresh, tasmin, )
    events = (tasmin > thresh) * 1
    return events.resample(time=freq).sum(dim='time')