生成器对象
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生成器对象是Python用来实现生成器迭代器的对象。它们通常通过迭代产生值的
函数来创建，而不是显式调用 "PyGen_New()" 或 "PyGen_NewWithQualName()"
。

PyGenObject

   用于生成器对象的C结构体。

PyTypeObject PyGen_Type

   与生成器对象对应的类型对​​象。

int PyGen_Check(PyObject *ob)

   Return true if *ob* is a generator object; *ob* must not be *NULL*.

int PyGen_CheckExact(PyObject *ob)

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

PyObject* PyGen_New(PyFrameObject *frame)
    *Return value: New reference.*

   Create and return a new generator object based on the *frame*
   object. A reference to *frame* is stolen by this function. The
   argument must not be *NULL*.

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

   Create and return a new generator 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*.
