Is the given id deprecated?  Returns nil if id is unlisted, or deprecation
status is undefined in the SPDX license list.

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 about what this means.

Is the given id FSF Libre?  Returns nil if id is unlisted, or FSF fsf-libre
status is undefined in the SPDX license list.

See https://github.com/spdx/license-list-XML/blob/main/DOCS/license-fields.md
for more details about what this means.

Returns the set of SPDX license identifiers that identify FSF Libre licenses
within the provided set of SPDX license identifiers (or all of them, if not
provided). See https://github.com/spdx/license-list-XML/blob/main/DOCS/license-fields.md
for more details about what this means.

Returns license 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 license 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 license identifiers?

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

Is the given id OSI approved?  Returns nil if id is unlisted, or osi-approval
is undefined in the SPDX license list.

See https://github.com/spdx/license-list-XML/blob/main/DOCS/license-fields.md
for more details about what this means.

Returns the set of SPDX license identifiers that identify OSI approved
licenses within the provided set of SPDX license identifiers (or all of them,
if not provided).

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

Note: identical to spdx.exceptions/version.