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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 read(self):
 """ Read in all unread lines and return them as a single string. """

        lines = self.readlines()
        if lines:
            try:
                return ''.join(lines)
            except TypeError:
                return ''.join(force_text(line) for line in lines)
        else:
            return None