Question

In a Python program I have a read-only property that I create using

bla = property(fget=_get_bla)

where _get_bla is a method defined in the class. When a program tries to write in this property

obj.bla = 1

I obviously get:

AttributeError: can’t set attribute

Is there a way to customize this exception? For example, I would like to change the message to

‘bla’ is a read-only property of class X

Thanks,

Answer 1

Yes, you can add next method to your class:

def set_bla(self, value):
    raise AttributeError("'bla' is a read-only property of class X")

and

bla = property(fget=get_bla, fset=set_bla)