What is a good practice to model Python properties in a UML class diagram?
Properties themselves are class objects, their getter and setter are class functions. From Outside the class they look like instance attributes. So, how would you suggest to present that in my class diagram?
Good practice is what works on your project.
In order to model Python properties you can add stereotyped getter and setter operations which indicate their use. The link between attribute and operation is usually done via a naming convention. Some tools offer internal linkage to make attributes properties with getters and setters.
If you are not using code generation you can also stereotype the attribute to indicate their use as properties (thus telling the coder to use @property) and leave away the operations. If you are using your own code generator this would work analogously. Tool embedded code generators might need the additional operations as described above.
How to model python properties in UML diagram