System - Remove duplicate functions

[colemanw]

Overview

Duplicate functions are already present in the parent classes and can be safely removed.

[civibot]

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Introduction for new contributors...

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PR commands & links...

• /rebase <branch-name> will rebase your branch and change the base of the PR.
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• 📖 Review standards
• 🗒️ Review template (brief or verbose)

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