Metadata about a language useful for training models
:ivar name: The human name for the language, in English.
:type name: str
:ivar iso_code: 2-letter ISO 639-1 if possible, 3-letter ISO code otherwise,
or use another catalog as a last resort.
:type iso_code: str
:ivar use_ascii: Whether or not ASCII letters should be included in trained
models.
:type use_ascii: bool
:ivar charsets: The charsets we want to support and create data for.
:type charsets: list of str
:ivar alphabet: The characters in the language's alphabet. If `use_ascii` is
`True`, you only need to add those not in the ASCII set.
:type alphabet: str
:ivar wiki_start_pages: The Wikipedia pages to start from if we're crawling
Wikipedia for training data.
:type wiki_start_pages: list of str