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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_all(self):
        '''
        Load all of them
        '''
        with self._lock:
            for name in self.file_mapping:
                if name in self.loaded_files or name in self.missing_modules:
                    continue
                self._load_module(name)

            self.loaded = True