import statistics
admin = {"admin":"ninja"}

studentDict = {'Jeff':[78,88,83],
               'Alex':[42,76,88],
               'Sam':[89,92,93]}
def enterGrades():
    nametoEnter = input("Student Name : ")
    gradetoEnter = input("Grade : ")

    if nametoEnter in studentDict:
        print("Adding Grade...")
        studentDict[nametoEnter] = (int(gradetoEnter))
    else:
        print("Student does not exist.")

def removeStudent():
    studentToRemove = input("What student would you like to delete?")
    if studentToRemove in studentDict:
        del studentDict[studentToRemove]
        print("removeing student")
    else:
        print("we did not find that student")
def studentAverage():
    peeraverage = input("What is the student you want to check?")
    if peeraverage in studentDict:
        print("getting average")
        avg = statistics.mean(studentDict[peeraverage])
        print(avg)

def addStudent():
    studentToAdd = input("What is the student you want to add?")
    if studentToAdd in studentDict:
        print("it appears that you have a copy, please enter a different name.")
    else:
        newstudentgrades = input("what is the person grades?")
        studentDict[studentToAdd] = (int(newstudentgrades))
        print('adding grades')
def listStudents():
    for key in studentDict.keys():
        print("Student: {}".format(key))

def main():
    print("""
    [1] - Enter Grades
    [2] - Delete Students
    [3] - Average Grade
    [4] - Exit
    [5] - Add Student
    [6] - List Students
    """)

    action = str(input("what is your command?"))

    if action == '1':
        enterGrades()
    elif action == '2':
        removeStudent()
    elif action == '3':
        studentAverage()
    elif action == '4':
        exit()
    elif action == '5':
        addStudent()
    elif action == '6':
        listStudents()
    else:
        print("you didn't enter a correct command.")

login = input('Username: ')
passw = input('Password: ')
if login in admin:
    if admin[login] == passw:
        print("welcome")
        while True:
            main()
    else:
        print("wrong password.")
else:
    print("wrong username")