There are several such videos on YouTube, I like this one best because they give the fullest explanation of their methods etc.
In summary, the bottle with 100% CO2 ended up 2C warmer than the bottle with normal air under a very bright light (giving off at least twice as much radiation as the sun does, from the point of view of the bottles).
Given the, I hope, undisputed logarithmic effect of increasing CO2 concentrations, I don't see how the increase from "pre-industrial levels" to current levels, from 0.03% TO 0.04%, could possibly have had any measurable effect.
But hey...
Debate Magazine
