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<?php

/**
  * Event Tickets: Remove "Not Going" as an RSVP option (i.e. make "Going" the only option)
  *
  * From https://gist.github.com/cliffordp/e8f2d63e6d26715cf18908f2102ba9fc
  *
  * @see: /wp-content/plugins/event-tickets/src/tribe/tickets_view.php
  */
function cliff_et_rsvp_remove_not_going_option( $options ) {
	// remove "Not Going" option
	unset( $options['no'] );
	
	return $options;
}
add_filter( 'event_tickets_rsvp_options', 'cliff_et_rsvp_remove_not_going_option', 10, 1 );