Hi, I want to concatenate boolean functions, i.e. lambda x: x < 10; during runtime with "and" and "or". However something like: d = lambda x: x < 10 d = lambda x: d(x) and (x %2 == 0) won't work and will end up in an infinite recursion (as far as I can figure out). How do you do something like that in python? Thanks in advance Yours Uwe