Gevent: NotImplementedError
Question: Why is gevent throwing this error? Running it in ipython, ubuntu 13

    
    
    In [1]: from gevent import monkey
    
    In [2]: monkey.patch_all()
    
    In [3]: The history saving thread hit an unexpected error (NotImplementedError('gevent is only usable from a single thread',)).History will not be written to the database.
    
    
    In [3]:
    


Answer: `ipython` uses a separate thread to save command history. Because `gevent`
patches threading methods, that pre-existing separate thread triggers the
gevent 'single thread' exception.

I would not use gevent in `ipython`; `ipython` is _not_ compatible with
gevent.

At the very least, try to patch out fewer things; try
`gevent.monkey.patch_all(thread=False)` and see if fewer things in `ipython`
break.

