A unprocessed document to be passed to the indexer.
This represents an item to be processed and stored in the search engine.
Each document will be processed by the indexer to generate a
ProcessedDocument, which can then be stored in the search engine index.
Note that some information in an UnprocessedDocument will not be
represented in the ProcessedDocument: therefore, it is not possible to
retrieve an UnprocessedDocument from the search engine index.
An unprocessed document is a simple container with two attributes:
- `fields` is a list of Field objects, or an iterator returning Field
- `id` is a string holding a unique identifier for the document (or
None to get the database to allocate a unique identifier automatically
when the document is added).
Definition at line 40 of file datastructures.py.