Pinta!

We had ran out of milk and No 3 kindly offered to go and buy some from the local shop. Now the local shop is not really local, and to get there you have to negotiate a level crossing (trains) and a busy downhill road. Now No 3 has become fiercely independent and I have had to let go, perhaps a little more than Shiv and I  would have at this stage. This being partly out of necessity. 
So I said yes please,  go and buy a pint of milk.
She also wanted to go on her bike, so I insisted that she wear a helmet, and she insisted that she would wear mine! So after adjusting my helmet to the best fit I could,  I gave her approximately the right money for what I assumed was the standard 1 Litre sized plastic milk carton. This was the size we always get because it fits in the fridge. So off she went. 
When she came back she handed me a 1 pint plastic carton of milk! 
I never knew you could still get pints of milk!
The last time I saw a pint of milk was many years ago when the milkman would leave pint glass bottles of milk on your doorstep each morning. 
So I thanked her, but muttered that this wouldn't last long but that was OK. Her reply -  'you said you wanted a pint of milk, so I bought what you asked for and here is your change'!