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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):
 """Add a new Section object to the config. Should be a subclass of _AbstractSection."""

        if not issubclass(section.__class__, _AbstractSection):
            raise TypeError("argument should be a subclass of Section")
        self.sections[section.get_key_name()] = section
        return section