An incoming email gets processed and saved to the database

An incoming email comes into `EmailProcessor`
`EmailProcessor` passes the email to `PackageGenerator`, and call `.generate`
`PackageGenerator` uses the `EmailAdapter` to clean up the data, and passes it to `Package` where it creates a new `Package` object, returning it to `EmailProcessor`.
Back in `EmailProcessor` it is saved in the database.

WOW!
For my own understanding: what is the role of key, here? It seems to be used to create db of things (such as spammer links) to strip out of the email text. Is that correct?