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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 _update_loaded_modules(self):
 """ Updates the loaded modules by checking if they are still in sys.modules """

        system_modules = sys.modules.keys()
        for module in list(self.loaded_modules):
            if module not in system_modules:
                self.processed_filepaths.pop(module)
                self.loaded_modules.remove(module)