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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_data(self, data):
 """ Update the data attribute, making sure it's a dictionary. """

        # Make sure a dict got passed it
        if not isinstance(data, type({})):
            raise TypeError("This attribute must be a dictionary.")
        # Set the attribute
        self.__dict__['data'] = DocumentDataDict(data)