If you are not comfortable with probing, you can sex the snake visually, though this is not an entirely accurate method. Female snakes have a very thin tail, that constricts almost immediately after the cloaca. Males on the other hand, have tails that are thicker and gradually get thinner, due to the fact that they have the hemipenes, which is located in the tail. I dont have any picture to show you, but you should be able to get a picture of a male and female next to each other on the net. Hope this helps.
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0.1 Normal Cornsnake
1.0 Sumatran Short Tail Python
1.1 Ball Pythons