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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_day_frequency(tasmax, thresh='30 degC', freq='YS'):
 r"""Frequency of extreme warm days Return the number of days with tasmax > thresh per period Parameters tasmax : xarray.DataArray Mean daily temperature [℃] or [K] thresh : str Threshold temperature on which to base evaluation [℃] or [K]. Default : '30 degC' freq : str, optional Resampling frequency Returns ------- xarray.DataArray Number of days exceeding threshold. Notes: Let :math:`TX_{ij}` be the daily maximum temperature at day :math:`i` of period :math:`j`. Then counted is the number of days where: .. math:: TN_{ij} > Threshold [℃] """

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