includes/class-freemius.php
private function is_premium_version_installed() {
            $premium_plugin_basename = $this->premium_plugin_basename();
            $premium_plugin          = get_plugins( '/' . dirname( $premium_plugin_basename ) );

            return ! empty( $premium_plugin );
        }
private function is_premium_version_installed() {
            $premium_plugin_basename = $this->premium_plugin_basename();
            $premium_plugin          = get_plugins( '/' . dirname( $premium_plugin_basename ) );

            return ! empty( $premium_plugin );
        }
private function is_premium_version_installed ( ) { $ premium_plugin_basename = $ this -> premium_plugin_basename ( ) ; $ premium_plugin = get_plugins ( '/' . dirname ( $ premium_plugin_basename ) ) ; return ! empty ( $ premium_plugin ) ; }
Check if the paid version of the module is installed.

@author Vova Feldman (@svovaf)
@since  2.2.0

@return bool
Check if the paid version of the module is installed .