In case you receive a similar error to this:
Fatal error: Call to undefined function get_editable_roles() in ~/public_html/example.com/wp-content/plugins/jetpack/modules/stats.php on line 219
Just visit the dashboard of your website (http://example.com/wp-admin/).
It will make the necessary calls to the Jetpack plugin and fix this error (this error is an initialization error).
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