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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 readline(self, limit=-1, delim=b'\n'):
 """Read a single line. If EOF is reached before a full line can be read, a partial line is returned. If *limit* is specified, at most this many bytes will be read. """

        self._check_readable()
        chunks = []
        while True:
            chunk = self._buffer.get_chunk(limit, delim)
            if not chunk:
                break
            chunks.append(chunk)
            if chunk.endswith(delim):
                break
            if limit >= 0:
                limit -= len(chunk)
                if limit == 0:
                    break
        if not chunks and not self._buffer.eof and self._buffer.error:
            raise compat.saved_exc(self._buffer.error)
        return b''.join(chunks)