main study tracker.py

def Add_subject():
    try:
        subject = input("Which subject do you want to add:")
        with open("subjects.txt","a") as file:
            file.write(subject +  "\n")

        with open("subjects.txt","r") as file:
            subjects = file.read()

        print("Subject added successfully")

    except Exception as e:
        print("Error",e)

def Remove_subject():
    try:
        with open("subjects.txt","r") as file:
            subjects = file.read().splitlines()

        for i, subject in enumerate(subjects, start=1):
            print(f"{i}:{subject}")

        remove = int(input("Which subject to remove(1/2/3, etc):"))
        index = remove - 1

        if remove > len(subjects):
            print("Subject does not exist")
        else:
            subjects.pop(index)

            with open("subjects.txt","w") as file:
                for s in subjects:
                    file.write(s + "\n")

    except Exception as e:
        print("Error:",e)

def View():
    try:
        with open("subjects.txt","r") as file:
            subjects = file.read().splitlines()

        for i,subject in enumerate(subjects,start=1):
            print(f"{i}.{subject}")

    except Exception as e:
        print("Error:",e)

def Chapters():
    try:
        with open("subjects.txt","r") as file:
            subjects = file.read().splitlines()

        for i, subject in enumerate(subjects, start=1):
            print(f"{i}:{subject}")

        add = int(input("Which subject to add chapters to(1/2/3, etc):"))

        if add > len(subjects):
            print("Subject does not exist")

while True:
    print("\nStudy Tracker\nWhat operation do you want to do?\n\n1.Add subject\n2.Remove subject\n3.View subjects\n4.Add/remove chapters\n5.Add/remove notes for subjects\n6.View chapters and notes\n7.log study sessions\n8.View progress\n9.Calculator(for math)\n")

    choice = input("Enter your choice:")
    if choice not in ["1","2","3","4","5","6","7"]:
        print("Enter a valid choice")
        continue

    if choice == "1":
        Add_subject()

    elif choice == "2":
        Remove_subject()

    elif choice == "3":
        View()