class Base(object): pass class A(Base): a = 1 b = 2 c = 3 class B(Base): a = 2 b = 2 class C(Base): b = 8 c = 6 def f(n): if n > 3: x = A elif n > 1: x = B else: x = C if n > 0: return x.a return 9 # __________ Entry point __________ def entry_point(argv): print f(int(argv[1])) return 0 # _____ Define and setup target ___ def target(*args): return entry_point, None if __name__ == '__main__': import sys entry_point(sys.argv)