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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 load_routes(self):
 """ Load all routes in project's folder 'controllers'. Ignore files with leading underscore (for example: controllers/_blog.py) """

        for file_name in os.listdir(os.path.join(self._project_dir, 'controllers')):
            # ignore disabled controllers
            if not file_name.startswith('_'):
                module_name = file_name.split('.', 1)[0]
                module_path = "controllers.{}".format(module_name)
                module = import_module(module_path)
                controllers = [getattr(module, x) for x in dir(module) if x != 'Controller' and x.endswith('Controller')]
                controller = controllers[0]
                self._routes[module_name] = controller
        return self._routes