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a few days ago I also struggled really hard to install it on my raspberry pi 3 ...

git clone https://github.com/steemit/steem-python.git cd steem-python pipenv install --three --dev # use --two instead of --three for Python 2.7 pipenv install .

I think this someone worked in the end but on my main windows machine I used a tutorial by @holger80.

thanks for pointing me to @holger80, it helped :)