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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, length=-1):
 """ Read ``length`` bytes from the file. If ``length`` is negative or omitted, read all data until EOF. :type length: int :param length: the number of bytes to read :rtype: string :return: the chunk of data read from the file """

        _complain_ifclosed(self.closed)
        # NOTE: libhdfs read stops at block boundaries: it is *essential*
        # to ensure that we actually read the required number of bytes.
        if length < 0:
            length = self.size
        chunks = []
        while 1:
            if length <= 0:
                break
            c = self.f.read(min(self.buff_size, length))
            if c == b"":
                break
            chunks.append(c)
            length -= len(c)
        data = b"".join(chunks)
        if self.__encoding:
            return data.decode(self.__encoding, self.__errors)
        else:
            return data