Key does not correctly work on class instance methods

[togakangaroo]

Consider this:

In [81]: 
class Foo:

  @AsyncTTL(time_to_live=10)
  async def getval(self): return random.random()

In [82]: await (fooA := Foo()).getval(), await fooA.getval(), await Foo().getval()
Out[83]: (0.9306262352193505, 0.9306262352193505, 0.9306262352193505)

The expectation is that you would get the same value for the first two but a different one for the third as the actual instance is different and therefore hash(self) is different.

The issue seems to be in the implementation of KEY which doesn't use hash at all if you're a class for some reason.