Doesn't tree have a way of iterating over nodes matching an xpath? tree.xpath(TARGET_XPATH) I beleive. Aa Point is the comprehension is flawed to start with.

Doesn't tree have a way of iterating over nodes matching an xpath? tree.xpath(TARGET_XPATH) I beleive. Aa Point is the comprehension is flawed to start with. If you need f(x) on both side, then f(x) should happen first, rather than doing it inside and assigning it. That requires a new user to know the if part (at the end) gets executed first, which is dirty.