pywt wheels need to be rebuilt with newer cython version

[nils-werner]

In Python 3.7 an ImportWarning will be issued when importing pyWt:

import pywt
../lib/python3.7/site-packages/pywt/__init__.py:16: in <module>
from ._extensions._pywt import *
pywt/_extensions/_pywt.pyx:1: in init pywt._extensions._pywt
???
pywt/_extensions/_dwt.pyx:7: in init pywt._extensions._dwt
???
ImportWarning: can't resolve package from __spec__ or __package__, falling back on __name__ and __path__

In my case it is tripping up pytest, which makes an error out of this warning, making the testsuite on my library fail.

As this issue is related to this one a workaround is to simply rebuild pywt from source, with an appropriately recent version of cython:

pip uninstall PyWavelets
pip install "cython>=0.29.0"
pip install -U --no-binary :all: PyWavelets

And as a final solution, the wheels should be rebuilt with this cython version.

[grlee77]

Thanks for raising the issue.
We have been planning to do a 1.0.2 bug fix release very soon (possibly even later this evening). The new wheels should get built with the latest Cython, so hopefully that will fix the issue.

[grlee77]

Closing this now that PyWavelets 1.0.2 has been released. Please reopen if you still encounter the issue.