There is some issue with closing the database connection, but I don’t understand why I can’t close the access and delete the database afterwards. I tried a lot of time, but I didn`t see information about my error.

I tried to describe the problem with deletion in the delete_database function, but it didn’t work out. The error that appears is:

Exception ignored in atexit callback: <function delete_database at 0x0000023EA47A8720>
Traceback (most recent call last):
  File "File name", line 71, in delete_database
    os.remove("University.db")
PermissionError: [WinError 32] The process cannot access the file because it is being used by another process: 'University.db

My code

import sqlite3
import os
def create_tables():
    with sqlite3.connect("University.db") as database:
        cursor = database.cursor()

        # Створення таблиць
        cursor.execute("""CREATE TABLE IF NOT EXISTS Students (
            student_id INTEGER PRIMARY KEY,
            first_name TEXT,
            last_name TEXT,
            age INTEGER,
            group_id TEXT,
            FOREIGN KEY (group_id) REFERENCES Groups(group_id)
        )""")

        cursor.execute("""CREATE TABLE IF NOT EXISTS Groups (
            group_id TEXT PRIMARY KEY,
            group_name TEXT
        )""")

        cursor.execute("""CREATE TABLE IF NOT EXISTS Courses (
            course_id INTEGER PRIMARY KEY,
            course_name TEXT
        )""")

        cursor.execute("""CREATE TABLE IF NOT EXISTS Teachers (
            teacher_id INTEGER PRIMARY KEY,
            first_name TEXT,
            last_name TEXT
        )""")

        cursor.execute("""CREATE TABLE IF NOT EXISTS Results (
            result_id INTEGER PRIMARY KEY,
            student_id INTEGER,
            subject_id INTEGER,
            teacher_id INTEGER,
            grade INTEGER,
            FOREIGN KEY (student_id) REFERENCES Students(student_id),
            FOREIGN KEY (subject_id) REFERENCES Subjects(subject_id),
            FOREIGN KEY (teacher_id) REFERENCES Teachers(teacher_id)
        )""")

        database.commit()

def add_student(first_name, last_name, age, group_id):
    with sqlite3.connect("University.db") as database:
        cursor = database.cursor()
        cursor.execute("INSERT INTO Students (first_name, last_name, age, group_id) VALUES (?, ?, ?, ?)",
                       (first_name, last_name, age, group_id))
        database.commit()

def get_student_info(student_id):
    with sqlite3.connect("University.db") as database:
        cursor = database.cursor()
        cursor.execute("SELECT * FROM Students WHERE student_id = ?", (student_id,))
        student_info = cursor.fetchone()
        return student_info

def get_all_students():
    with sqlite3.connect("University.db") as database:
        cursor = database.cursor()
        cursor.execute("SELECT * FROM Students")
        all_students = cursor.fetchall()
        return all_students

def delete_database():
    if os.path.exists("University.db"):
        os.remove("University.db")
        print("The database file has been deleted.")
    else:
        print("The database file does not exist.")

atexit.register(delete_database)

create_tables()

while True:
    option = int(input("Select an option:n1. Information about one studentn2. Information about all studentsn3. Exit"))

    if option == 1:
        student_id = input("Enter the student number: ")
        student_info = get_student_info(student_id)
        print(student_info)
    elif option == 2:
        all_students = get_all_students()
        for student in all_students:
            print(student)
    elif option == 3:
        break
    else:
        print("Incorrect. Try again!")