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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 set_type(self, weather_type):
 """Set the weather type. Args: weather_type (str):
 The weather type. """

        weather_type.lower()
        exists = self.has_type(weather_type)
        if exists:
            self.add_string_parameters(weather_type)