协程对象
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3.5 新版功能.

协程对象是使用 "async" 关键字声明的函数返回的。

PyCoroObject

   用于协程对象的C结构体。

PyTypeObject PyCoro_Type

   与协程对象对应的类型对​​象。

int PyCoro_CheckExact(PyObject *ob)

   Return true if *ob*'s type is *PyCoro_Type*; *ob* must not be
   *NULL*.

PyObject* PyCoro_New(PyFrameObject *frame, PyObject *name, PyObject *qualname)
    *Return value: New reference.*

   Create and return a new coroutine object based on the *frame*
   object, with "__name__" and "__qualname__" set to *name* and
   *qualname*. A reference to *frame* is stolen by this function.  The
   *frame* argument must not be *NULL*.
