Full stacktrace:
➜ ~ pip install virtualenv Traceback (most recent call last): File \"/usr/bin/pip\", line 11, in sys.exit(main())
I had the same problem, and "export LC_ALL=c" didn't work for me.
"export LC_ALL=c"
Try export LC_ALL="en_US.UTF-8" (it will work).
export LC_ALL="en_US.UTF-8"