Please help me to draw a sequence diagram for this use-case, thank you.

Use Case Name: Maintain Class Records ID Importance Level Primary Actor: Staff Member Use Case Type: Detail, Essential Stakeholders and Interests: The staff member maintains (i.e., creates, reads, modifies, and deletes) class records for a given course. Brief Description: This CRUD (create, read, update, and delete) use case maintains the educational institution's records of the classes it offers (for a given course). It provides the staff member actor with complete control over the creation, deletion, modification, and reading of class records for a given course. Trigger: A staff member wanting to maintain the class records for a given course Type Relationships Association with the staff member actor . Include relationship to the log in into the Courses and Classes Records use case Normal Flow of Events 1. 2. 3. The staff member enters the course whose classes are to be maintained. The system responds with a list of all classes (either online or face-to-face) for the entered course. The staff member then selects one of the classes and commands the system to perform one of the following operations on the selected class a) Delete the selected clasS b) Modify certain fields in the selected class. Alternatively, the staff member actor can create a new class offering for the course, classify it as an online or face-to-face class, and then enter the required information for all kinds of classes and for each classification as follows: 4. a) For all classes i. Class begin date and class end date b) For online classes i. Class URL ii. Class browser c) For face-to-face classes i. Class building ii. Class room SubFlows Alternate/Exceptional Flows Alternate Flows: Each one of the CRUD operations is considered an alternate flow through the use case. Exceptional Flows: This is when the course entered does not exist in the system Courses & Classes Records Class Diagram Course -CourselD: string CourseName: string CreditHours: int Description: string CreateCourse(string): type GetcourseByCourseID(string) Undate Course(string) DeleteCourse(string) SetclassesForACourse(string) Class +CourselD: string BeginDate: date EndDate: date +CreateOnlineClass UndateOnlineClass. ) +DeleteOnlineClass +UndateFace ToFaceClass. DeleteFace ToFaceClass Extends Extends Online Face ToFace +Building: string URL: string +Browser string Room:string