Seven o’clock on a Monday night and I am standing in the House of Commons , nursing a glass of vinegary white wine. All around me are people doing the same, though it’s polite sipping rather than getting sloshed. Waiters ferry bottles between the terrace function rooms, where MPs are hosting dinners or campaign launches like the one I’m at. Between the clanging division bells summoning MPs for votes that will go on tonight until gone 11pm, the Strangers’ bar is doing its usual trade. Welcome to the working-but-not-quite-working time of night, where professional shades into slightly social; a fuzzy grey area that can sometimes get too fuzzy for everyone’s good. But it can also be a surprisingly productive time, as I realised only after having a baby for whom I needed to get home in the evenings, and realising how painfully out of the loop that made me. For Hannah Spencer, the new Green MP for Gorton and Denton, parliament’s drinking culture was clearly a shock .…