Is the given id deprecated?

See https://github.com/spdx/license-list-XML/blob/main/DOCS/faq.md#what-does-it-mean-when-a-license-id-is-deprecated
for more details on what this means.

Returns exception information for the given identifier as a map, or nil if
there isn't one (e.g. the id is nil or invalid).

The set of all exception ids.

Initialises this namespace upon first call (and does nothing on subsequent
calls), returning nil. Consumers of this namespace are not required to call
this fn, as initialisation will occur implicitly anyway; it is provided to
allow explicit control of the cost of initialisation to callers who need it.

Note: this method has a substantial performance cost.

Is the given id one of the listed SPDX exception identifiers?

Returns the set of exception ids that identify current (non-deprecated)
exceptions within the provided set of SPDX exception identifiers (or all of
them, if not provided).

The version of the exception list (a String in major.minor format).

Note: identical to spdx.licenses/version.