You can also try soaking him in a small amount (1/4 to 1/2 inch) of warm water. Place a small piece of cork bark or rock for him to rub against in the water and close him up for a couple hours. The water will soften the shed and as he climbs around he'll rub against the cork.

Hand shedding (using either water, mineral oil, or commercially available "shed-aid" can also work, but be very very gentle so as not to hurt or stress the snake.

Try soaking him daily for 1-2 hours as described above for 2-3 days and see if you make any progress.
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lost in the jungle somewhere
Z