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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 _preload_range(self):
 """Preload data for reading"""

        queue = self._read_queue
        size = self._buffer_size
        start = self._seek
        end = int(start + size * self._max_buffers)
        workers_submit = self._workers.submit
        indexes = tuple(range(start, end, size))

        # Drops buffer out of current range
        for seek in tuple(queue):
            if seek not in indexes:
                del queue[seek]

        # Launch buffer preloading for current range
        read_range = self._read_range
        for seek in indexes:
            if seek not in queue:
                queue[seek] = workers_submit(read_range, seek, seek + size)