VOID

def create_connection(db_file):
    """ create a database connection to the SQLite database
        specified by db_file
    :param db_file: database file
    :return: Connection object or None
    """
    conn = None
    try:
        conn = sqlite3.connect(db_file)
        return conn
    except Error as e:
        print(e)

    return conn


def create_table(conn, create_table_sql):
    """ create a table from the create_table_sql statement
    :param conn: Connection object
    :param create_table_sql: a CREATE TABLE statement
    :return:
    """
    try:
        c = conn.cursor()
        c.execute(create_table_sql)
    except Error as e:
        print(e)
def main():
    
    database = 'instance/test.db'
    sql_create_grades_table = """ CREATE TABLE IF NOT EXISTS projects (
                                        id integer PRIMARY KEY,
                                        name text NOT NULL,
                                        begin_date text,
                                        end_date text
                                    ); """

    # create a database connection
    conn = create_connection(database)

    # create tables
    if conn is not None:
        # create tasks table
        create_table(conn, sql_create_grades_table)
    else:
        print("Error! cannot create the database connection.")

Schema

import sqlite3

database = 'instance/test.db'

def schema():
    
    conn = sqlite3.connect(database)

    cursor = conn.cursor()
    
    results = cursor.execute("PRAGMA table_info('grades')").fetchall()

    for row in results:
        print(row)

    conn.close()
    
schema()

Create

import sqlite3

def create():
    subject = input("Enter your class:")
    grade = input("Enter your letter grade:")
    
    # Connect to the database file
    conn = sqlite3.connect(database)

    # Create a cursor object to execute SQL commands
    cursor = conn.cursor()

    try:
        # Execute an SQL command to insert data into a table
        cursor.execute("INSERT INTO grades (_subject, _grade) VALUES (?, ?)", (subject, grade))
        
        # Commit the changes to the database
        conn.commit()
        print(f"A new subject record {uid} has been created")
                
    except sqlite3.Error as error:
        print("Error while executing the INSERT:", error)


    # Close the cursor and connection objects
    cursor.close()
    conn.close()
    
create()

Error while executing the INSERT: no such table: grades