1.2 Rule of precedence between superclasses of a different origin
If several superclasses have attributes/methods with the same name but with a
different origin, the attribute/method of the first superclass is inherited by the
subclass. For example, consider the subclass SalesStaffClient in Figure 26.10,
which inherits from SalesStaff and Client. Both these superclasses have an attribute
telNo, which is not inherited from a common superclass (which in this case is
Person). In this instance, the definition of the telNo attribute in SalesStaffClient is
inherited from the first superclass, namely SalesStaff.