Mutability problem when subclassing tuple

[Edward C. Jones]

# What restrictions are there when subclassing "tuple" or other
# types that create immutable objets?

# I want this class to contain "(1, 2)".
class simple(tuple):
     def __init__(self, text):
         tuple.__init__(self, [1, 2])

# "simple2" works, therefore "simple" has a mutability problem.
class simple2(list):
     def __init__(self, text):
         list.__init__(self, [1, 2])

# Here is an example that shows what I am trying to do.
# I want to create the tuple in "example" within "__init__" by
# processing "text". In this case the tuple should be "(1, 2)".
class example(tuple):
     def __init__(self, text):
         alist = self.process(text)
         tuple.__init__(alist)

     def process(self, text):
         return [1, 2]

if __name__ == '__main__':
     print simple('abc')  # Prints "('a', 'b', 'c')".
     print simple2('abc')  # Prints "[1, 2]".
     print example('abc')  # Prints "('a', 'b', 'c')".