I needed to link some page explaining what inlineCallbacks and deferredGenerator are, and ... failed to find one. So here is a short explanation and the example code (working scripts).

Code size comparison: raw deferreds - 29 lines, deferredGenerator - 26 lines, inlineCallbacks - 17 lines (non-empty lines, lookup function measured).

VirtualEnv is of incredible help for anybody using frequently changing new Python frameworks. Wanna test one project with Pylons 0.9.5 and another with Pylons 0.9.6? Need SQLAlchemy 0.4.3 while packaged 0.4.1 is required by some other app? Need to install some libraries without root access? No problem.

The only problem is somewhat unclear documentation. So here is my short recipe.