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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 filter_by_keyword(self, keyword):
 """Return a list of ddys that have a certain keyword in their name. This is useful for selecting out design days from a ddy file that are for a specific type of condition (for example, .4% cooling design days) """

        filtered_days = []
        for des_day in self.design_days:
            if keyword in des_day.name:
                filtered_days.append(des_day)
        return filtered_days