Function: Get courses by instructors

Function: Determine if an instructor is a specific course author | Owner

Filter Hook: Filter the output of dozent_is_course_author();

Function: Get the rating of an instructor

Function: Get total students count by an instructor

Function: get all completed status of earning

Function: Get the earning statements by calling this funcitons

Function: Get all questions by quiz

Function: Get single quiz question by question ID

Filter Hook: Filter the dozent_get_question_types() return