Installer fails with "error: could not create '/usr/local/lib/python2.7/dist-packages/grpc': Permission denied"

[wjarek-zz]

Running

curl -fsSL https://goo.gl/getgrpc | bash -s python

(as non-privileged user) results in the following error:

running install_lib

creating /usr/local/lib/python2.7/dist-packages/grpc

error: could not create '/usr/local/lib/python2.7/dist-packages/grpc': Permission denied

I could not figure out how to pass the --user flag (or similar) to it. Everything else was properly installed in $HOME/.linuxbrew but the last step of copying the Python libraries failed.
Is there a workaround?