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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 add_section(self, section):
 """You can add section inside a Element, the section must be a subclass of SubSection. You can use this class to represent a tree. """


        if not issubclass(section.__class__, SubSection):
            raise TypeError("Argument should be a subclass of SubSection, \
                             not :" + str(section.__class__))
        self.sections[section.name] = section
        return section