[pypy-issue] Issue #2915: Importing lxml on PyPy3.6 nightly fails (pypy/pypy)

[Donald Stufft]

New issue 2915: Importing lxml on PyPy3.6 nightly fails
https://bitbucket.org/pypy/pypy/issues/2915/importing-lxml-on-pypy36-nightly-fails

Donald Stufft:

When installing and then importing lxml on PyPy3 3.6 (`pypy-c-jit-95165-6ffaea666f35-linux64.tar.bz2`) an error is generating when trying to import `lxml.etree`.


```
>>>> import lxml.etree
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: /opt/warehouse/site-packages/lxml/etree.pypy3-61-x86_64-linux-gnu.so: undefined symbol: _PyErr_FormatFromCause
```

I'm not sure if this bug lies with PyPy or lxml, but figured I'd start here.