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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):
 """ If section exists, returns log, otherwise adds section and returns list of sections. """

        # check if section already exists
        if not self.config.has_section(section):
            self.config.add_section(section)
            # return updated sections
            return (True, self.config.sections())
        return (False, 'Section: ' + section + ' already exists')