Some examples that come to mind: You can inspect the call stack, and get a list of local variables of your callers. You can assign to object.__class__ to dynami

Some examples that come to mind: You can inspect the call stack, and get a list of local variables of your callers. You can assign to object.__class__ to dynamically change an existing object's class at runtime. You can overwrite every operator, including obj.field access, dynamically at runtime (including changing an existing class)