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function set_username($current_user, $username) {
  $error = false;
  $message = '';
  $uname = 0;

  if ( $username ) {
    if ( $username !== $current_user->user_login ) {
			if ( username_exists( $username ) ) {
				$error = true;
				$message = 'Username already exists';
			} else {
				global $wpdb;

				$query = $wpdb->query( $wpdb->prepare( "UPDATE $wpdb->users SET user_login = %s WHERE user_login = %s", $username, $current_user->user_login ) );
				if ( $query ) {
					$uname = 1;
				}
			}
		}
  } else {
		$error = true;
		$message = 'Username is a required field.';
  }
  return array("message" => $message, "error" => $error);
}