[x] Update CHANGELOG.rst for each commit separately:
Pay attention to write entries under the "Unreleased" section.
Mark all breaking changes as "BACKWARD INCOMPATIBLE:" and put them
before non-breaking changes.
If a commit modifies a feature listed under "Unreleased" section,
it might be sufficient to modify the existing CHANGELOG entry from previous
commit(s).
[ ] Bump the process version:
MAJOR version (first number): Backward incompatible changes (changes
that break the api/interface). Examples: renaming the input/output, adding
mandatory input, removing input/output...
MINOR version (middle number): add functionality or changes in a
backwards-compatible manner. Examples: add output field, add non-mandatory
input parameter, use a different tool that produces same results...
PATCH version (last number): changes/bug fixes that do not affect
the api/interface. Examples: typo fix, change/add warning messages...
[ ] All inputs are used in process.
[ ] All output fields have a value assigned to them.
in Variant model