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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 start_indexing(self):
 """ Read all the files and tokenize their text into words and accumulate all the words in a list. """

        for filepath in self.filepaths:
            with open(filepath) as fp:
                blob = fp.read()
                self.words.extend(self.tokenize(blob))