How do I invalidate @cached_property in django

Just del it as documentation says. It will lead to recalculation on next access.

class SomeClass(object):
    
    @cached_property
    def expensive_property(self):
         return datetime.now()

obj = SomeClass()
print obj.expensive_property
print obj.expensive_property # outputs the same value as before
del obj.expensive_property
print obj.expensive_property # outputs new value

For Python 3 it’s the same use of del. Below is an example of a try/except block.

try:
    del obj.expensive_property 
except AttributeError:
    pass