How to know if an object has an attribute in Python

Question

Is there a way in Python to determine if an object has some attribute? For example:

>>> a = SomeClass()
>>> a.someProperty = value
>>         


        

Answer 1

hasattr() is the right answer. What I want to add is that hasattr() can also be used well in conjunction with assert (to avoid unnecessary if statements and make the code more readable):

assert hasattr(a, 'property'), 'object lacks property' 

As stated in another answer on SO: Asserts should be used to test conditions that should never happen. The purpose is to crash early in the case of a corrupt program state.