OSX py35 build failing

[jzaremba]

PyWavelets doesn't have pre-build for OSX py35 and build requires numpy.

Collecting PyWavelets>=0.4.0 (from scikit-image)
  Downloading https://files.pythonhosted.org/packages/4b/df/3fff2a8b96ef7df6e4e8642fb7569c3717ae562dd76afe0f96525c0af784/PyWavelets-0.5.2.tar.gz (4.4MB)
    Complete output from command python setup.py egg_info:
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/private/tmp/pip-install-q5fxej7s/PyWavelets/setup.py", line 12, in <module>
        from numpy import get_include as get_numpy_include
    ModuleNotFoundError: No module named 'numpy'