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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 prepare_to_generate(self, data_dir, tmp_dir):
 """Make sure that the data is prepared and the vocab is generated."""

    self.get_or_create_vocab(data_dir, tmp_dir)
    self.train_text_filepaths(tmp_dir)
    self.dev_text_filepaths(tmp_dir)