def __fill_buffer(self, size=<NUM_LIT:0>):
read_size = min(max(size, self.__buffer_size), MAX_BLOB_FETCH_SIZE)<EOL>self.__buffer = fetch_data(self.__blob_key, self.__position,<EOL>self.__position + read_size - <NUM_LIT:1>)<EOL>self.__buffer_position = <NUM_LIT:0><EOL>self.__eof = len(self.__buffer) < read_size<EOL>
Fills the internal buffer.

        Args:
          size: Number of bytes to read. Will be clamped to
            [self.__buffer_size, MAX_BLOB_FETCH_SIZE].