Describe the bug

As in the title.

Similar: #5160 (has been fixed now)

Code to reproduce the behaviour:

cdef class F:
	def __get__(self, a, b=None):
		print(b)

F().__get__(1)

Expected behaviour

Works well.

OS

Linux

Python version

3.11

Cython version

3.0.11 I believe?

Additional context

Side note, currently

cdef class F:
	def __get__(self, a, b):
		print(b)

is accepted, but in Cython you can call it omitting the last argument. This is currently used in SageMath code base (see sage/src/sage/misc/cachefunc.pyx), so making it raise error (for Python compatibility) would break SageMath.

I think it's still better to raise error when the code does not specify default argument though (to avoid confusing behavior), but a deprecation period is needed.