Not so long time ago I started using GAE (Google AppEngine) with Python, and so many questions came, some hard to find on google. This multipart tutorial is for guys like me, so you don’t need to google anymore to find what you need to start with writing python apps on GAE.
Chapters:
1. Registering an account
2. Creating your first application
Registering an account
1. go to http://appengine.google.com and you will be prompted to login into GAE with screen like this: 
2. If you don’t have Google account yet – you have to create one now clicking red “Sign up” button in top right part of screen:
3. After logging into AppEngine, you will see view like this:
4. Just press “Create Application” and if you just created you AppEngine account you have to verify it using your cell number:
Creating your first application
If you already verified you account, you will be prompted to enter application data:
And now some description of this form, since there are some important parts:
1. First you can choose you app name, if you plan to make it public, this is one of most important steps, you can check if choosen name is free clicking “Check Availability”, and such message:
you have to choose another name, so we did:
2. Next step is application title:
not so important unless you’ll go public
3. Now the security part, for our first app just leave default value:
4. Same with storage data – for our first app, default value is ok, also master/slave is not supported anymore in python 2.7 and above:
4. Since we’re done here, push “Create Application” and your first app is created:
now you have to write it.