pypy heapq c implementation

Question

为什么heapq的c模块不能用于pypy，我该怎么做才能使它可用？

即

Python 2.7.13 (c5b147d52043, Jan 01 2018, 23:13:26)
[PyPy 5.11.0-alpha0 with GCC 6.3.0 20170516] on linux2
Type "help", "copyright", "credits" or "license" for more information.
And now for something completely different: ``"translation toolchain" =
"RPyther"?  to write inteRPythers in''
>>>> import heapq
py version

当我修改源代码时：

try:
    from _heapq import *
    print "c version"
except ImportError:
    print "py version"
    pass

然而是cpython：

Python 2.7.13 (default, Nov 24 2017, 17:33:09) 
[GCC 6.3.0 20170516] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import heapq
c version
>>> exit()

感谢，

克里斯