snakes when they are constipated get an really odd lumpy look and often seem bloated and airy it is not normal at all and as far as I know always very odd looking.
I have had one become constipated (X-rays determined) in my case it was from a very large amount of substrate ingestion (cyprus mulch) she has one eye and horrible aim and got a full mouth full and decided to swallow it before and during my attempts to extract it. Rare and usually due to some very odd event.
The xray is cool however.
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