hasattr returns False for an object whose __get__ throws AttributeError.

has_no_attr.py

class A:
    pass

class B:
    def __get__(self, instance, cls=None):
        raise AttributeError()

class C:
    a = A()
    b = B()

>>> C().a
<A object at 0x7fe55bdce6d0>

>>> hasattr(C(), 'a')
True

>>> C().b
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "<console>", line 3, in __get__
AttributeError

>>> hasattr(C(), 'b')
False  # without the error!