x : int = 3
print('x =',x, type(x))
x = "forty"            # type error if run through mypy or pylance
print('x =',x, type(x))


y : int|str = 3        # y can be either of two types
y += 3                 # type error if run through mypy or pylance: works for int but not str
if isinstance(y, int): # check if it is one of those types; enables type-specific operations
  y += 3
else:
  y += ' three'