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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 sky_temperature(self):
 """Return annual Sky Temperature as a Ladybug Data Collection. This value in degrees Celcius is derived from the Horizontal Infrared Radiation Intensity in Wh/m2. It represents the long wave radiant temperature of the sky Read more at: https://bigladdersoftware.com/epx/docs/8-9/engineering-reference /climate-calculations.html#energyplus-sky-temperature-calculation """

        # create sky temperature header
        sky_temp_header = Header(data_type=temperature.SkyTemperature(), unit='C',
                                 analysis_period=AnalysisPeriod(),
                                 metadata=self._metadata)

        # calculate sy temperature for each hour
        horiz_ir = self._get_data_by_field(12).values
        sky_temp_data = [calc_sky_temperature(hir) for hir in horiz_ir]
        return HourlyContinuousCollection(sky_temp_header, sky_temp_data)