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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 get_wind_url(self):
 """Get wind arrow url."""

        wind_direction = self.f_d.get('wind_direction', None)
        if wind_direction is not None:
            rounded = int(5 * round(float(wind_direction)/5))
            return WIND_ARROW_URL.format(rounded)