python postgres游标时间戳问题

import psycopg2
from datetime import datetime

conn = psycopg2.connect(database="mydb", user="myuser", password="mypassword", host="localhost", port="5432")
cur = conn.cursor()

order_time = datetime(2021, 1, 1, 12, 0, 0)
cur.execute("INSERT INTO orders (order_time) VALUES (%s)", (order_time,))

conn.commit()
conn.close()

import psycopg2

conn = psycopg2.connect(database="mydb", user="myuser", password="mypassword", host="localhost", port="5432")
cur = conn.cursor()

cur.execute("SELECT order_time FROM orders WHERE id = 1")
order_time = cur.fetchone()[0]

conn.close()