General remarks

For Python classes the following statements apply:

 There is multiple inheritance.
 All class members are public.
 Base class members can be redefined in a derived class.
 Classes should be derived from object to be compliant with new-style classes intoduced in Python2.2.
 The methods object is the first argument (e.g. self)
 x.f() is exactly equivalent to MyClass.f(x)
 The contructor does not return a value. Therefore it has to raise an exception, if something went wrong.