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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 tx_tn_days_above(tasmin, tasmax, thresh_tasmin='22 degC', thresh_tasmax='30 degC', freq='YS'):
 r"""Number of days with both hot maximum and minimum daily temperatures. The number of days per period with tasmin above a threshold and tasmax above another threshold. Parameters tasmin : xarray.DataArray Minimum daily temperature [℃] or [K] tasmax : xarray.DataArray Maximum daily temperature [℃] or [K] thresh_tasmin : str Threshold temperature for tasmin on which to base evaluation [℃] or [K]. Default : '22 degC' thresh_tasmax : str Threshold temperature for tasmax on which to base evaluation [℃] or [K]. Default : '30 degC' freq : str, optional Resampling frequency Returns ------- xarray.DataArray the number of days with tasmin > thresh_tasmin and tasmax > thresh_tasamax per period Notes ----- Let :math:`TX_{ij}` be the maximum temperature at day :math:`i` of period :math:`j`, :math:`TN_{ij}` the daily minimum temperature at day :math:`i` of period :math:`j`, :math:`TX_{thresh}` the threshold for maximum daily temperature, and :math:`TN_{thresh}` the threshold for minimum daily temperature. Then counted is the number of days where: .. math:: TX_{ij} > TX_{thresh} [℃] and where: .. math:: TN_{ij} > TN_{thresh} [℃] """

    thresh_tasmax = utils.convert_units_to(thresh_tasmax, tasmax)
    thresh_tasmin = utils.convert_units_to(thresh_tasmin, tasmin)
    events = ((tasmin > (thresh_tasmin)) & (tasmax > (thresh_tasmax))) * 1
    return events.resample(time=freq).sum(dim='time')