Yes. I have repeated the process and have followed every step. I noted this error this time:
Command "/Users/kent/miniconda3/envs/qiime2-2017.11/bin/python -u -c "import setuptools, tokenize;file='/private/var/folders/jl/q7f85rnn1rggqpyv12ld1m7m0000gn/T/pip-build-kh5sxagg/greenlet/setup.py';f=getattr(tokenize, 'open', open)(file);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, file, 'exec'))" install --record /var/folders/jl/q7f85rnn1rggqpyv12ld1m7m0000gn/T/pip-ls73iir4-record/install-record.txt --single-version-externally-managed --compile" failed with error code 1 in /private/var/folders/jl/q7f85rnn1rggqpyv12ld1m7m0000gn/T/pip-build-kh5sxagg/greenlet/
If I continue I get the same result above.