Baseline existing database”翻译为'基准线现有数据库”，示例代码如下：

import sqlite3
 
# Create a connection to the database
conn = sqlite3.connect('existing_database.db')
 
# Create a cursor object
cur = conn.cursor()
 
# Set the baseline for the existing database
cur.execute('CREATE TABLE baseline (id INTEGER PRIMARY KEY, baseline_value TEXT)')
 
# Insert the baseline value for the existing database
cur.execute('INSERT INTO baseline VALUES(?, ?)', (1, 'baseline_value_here'))
 
# Commit the changes to the database
conn.commit()
 
# Close the database connection
conn.close()