Description

PR merges preliminary steps to stable release v3.0.0.

Motivation and Context

Related Issue

PR fixes the following issue: -

Type of change

• This change requires a documentation update;

Checklist:

• I've done a self-review of my code;
• I've made corresponding changes to the documentation;
• I've made sure my changes generate no warnings;
• mypy returns no errors when run on the root package;

• I've run black to format my code;
• I've run isort to format my code's import statements;
• flake8 reports no errors when run on the entire code base;