Despite the rather quality poor photos, it can be positively identified as a Keelback. It is a young animal and lacks some of the attributes of adults. Nevertheless, by magnifying and then adjusting the contrast and brightness of the photo showing the head slightly, it is possible to discern the loreal scale. Mention has already been made of labials scales and ventral scales. The length of tail immediately rules out the Whip Snake and Tree Snake possibilities mentioned – far too short. The labial scales have dark edges and the line of the jaw is curved upwards near the angle of the jaw and not straight. The body is also too robust for it to be a CTS. The relatively large eye is due partially to its age as is the degree of protrusion of the eyes. I could not discern any clear keels on scales but ascribe this to a combination of age and limitations of the photograph.
It may help in future to take photos in full sun but not in a reflective plastic container. Also, a verbal description of appearance would really help as we cannot see that which you can – colour, features, pattern, size, behaviour, scalation or the like.
The advice not to assume a snake is a Keelback, despite looking just like one, is sagacious. Rough-scaled Snakes are a dead ringer for Keelbacks for those not familiar with the subtle differences. They are highly venomous and their toxins are particularly quick acting. Absolutely not a mistake you want to make!
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