Jupyterlab没有Tab和Cython类的自动补全

Question

我对带有cython类的Tab感兴趣（请参阅下文）。 制表符完整仅在第一级起作用：

A1  = A()
A1. <= Tab shows now optimizer 
A1.optimizer. <= Tab shows nothing :(

以下我的Cython类缺少哪些功能，Tab完全可以使用？常规Python类也是如此吗？

cdef class optimizer():

    cdef:
        uint32_t u32_error

    def __init__(self):
        pass

    def __cinit__(self):
        self.u32_error = 0

    def __dealloc__(self):
        pass

    cdef uint32_t u32_calc_error(self, bool_t* x, bool_t* ref, uint32_t N):

        return 42

    cpdef uint32_t optimize(self):
        #self.u32_calc_error
        self.u32_error += 1
        return self.u32_error

    @property
    def error(self):
        return self.u32_error

cdef class A(B):
    """
    File: A.pxd
    'Optimizer' 
    cdef class A(B):
        ...
        ...

    """

    cdef:
        public optimizer optimizer

    def __cinit__(self, int N = 1):
        self.optimizer = optimizer()

    def __dealloc__(self):
        pass

    def __init__(self, int N = 1):
        super().__init__(N = N)