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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_path(self, path):
 """ Adds a new path to the list of searchable paths :param path: new path """


        if os.path.exists(path):
            self.paths.add(path)
            return path
        else:
            #logger.debug('Path {} doesn\'t exist'.format(path))
            return None