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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 from_json(cls, data):
 """Create a DDY from a dictionary. Args: data = { "location": ladybug Location schema, "design_days": [] // list of ladybug DesignDay schemas} """

        required_keys = ('location', 'design_days')
        for key in required_keys:
            assert key in data, 'Required key "{}" is missing!'.format(key)

        return cls(Location.from_json(data['location']),
                   [DesignDay.from_json(des_day) for des_day in data['design_days']])