Help: what is "mixed spices"

I have got a (British) recipy for a cake. One of the ingredients is “mixed spices”.

What is it, where can I get it, can I mix them spices myself?

I can’t remember sepecifically seeing mixed spice in the supermarkets here, but I’m sure some of them will have it. If they don’t, here’s a list of ingredients and the proportions you need. I’ve bought all of the listed ingredients here in Taipei.

Thanks, Sandman.