It works for me (Sage 7.1.beta3 complied on Debian jessie 64bit, run from the command line). Could you please give us some informations so that someone can try to reproduce your problem:
- which version of Sage did you use ?
- which OS ?
- did you install Sage from the binaries, and which ones ?
- did you compile Sage yourself ?
- which notebook did you use (Sage notebook or jupyter notebook) ?
- did you use the command line ?
- which command did you type precisely to get the error ?
- which error message did you get ?
- ... ?