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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_data(self):
 # type: () -> ByteString """ Reads all the data in the input stream :return: The read data """

        try:
            size = int(self.get_header("content-length"))
        except (ValueError, TypeError):
            size = -1

        return self.get_rfile().read(size)