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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 data(self):
 """ Read all of the documents from disk into an in-memory list. """

        def read(path):
            with open(path, 'r', encoding='UTF-8') as f:
                return f.read()

        return [
            read(f) for f in self.files
        ]