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I need help understanding how to code this in Java Part one of this project requires you to implement the complete class template for three classes: Student, Node, and DList. Each class is discussed below. Your code in main should only instantiate an object of each type. No other code should appear in main. Class Templates: Student: this class consists of three member variables - the name of the student, the sum of the student's grades, and the number of grades. The methods must include a default constructor and accessors and mutators for each member variable. Node: this class contains three member variables - a previous node reference, next node reference and a Student reference as the data portion. All appropriate methods are required as discussed in class. DList: this class will contain two member variables - a head and tail reference to Node. You must provide the following methods: default constructor, addHead, addTail, find Student, removeHead, remove Tail, printList. The method find Student will search for the student represented by the name passed in as the argument and if found, return the student object; otherwise, it should return null. Part 2: For this part of the assignment, you will use the objects you created to keep track of student grades. You will use a data file to load your DList with starting values. The file will be in the following format: studentname sumofgrades countofgrades Use a sentinel loop pattern to allow a user to choose an option from a menu allowing them to update a student record, remove a student record, display student information for all students, display a particular student's average grade, or exit. Some of these options will require additional information from the user. Modularize main as necessary