Google App Engine （Python）でメールを受信する普通の例

Receiving Email - Google App Engine - Google Code

Receiving Email

Email messages sent to your app are implemented as HTTP requests. To process incoming email messages, you associate email addresses with script handlers in your app configuration, then include the handlers in your app's code. Incoming email generates HTTP requests, which are passed to the appropriate scripts.

こっちが標準的なやり方だった
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