import random

class A:
  pass

class B:
  pass

MysteryClass = A if False else B

# a: A = MysteryClass()  -> fails!

MysteryClass2 = A if random.randint(1, 10) > 5 else B

# a: A = MysteryClass2()  -> fails! error: Incompatible types in assignment (expression has type "object", variable has type "A")

class C(A):
  pass

class D(A):
  pass

NewMysteryClass = C if random.randint(1,10) > 5 else D

a: A = NewMysteryClass()  # a is of class A