Python でのexecutemanyとシーケンスの使用法を解析するチュートリアル

import sqlite3 
persons=[ 
  ("Jim","Green"), 
  ("Hu","jie") 
  ] 
conn=sqlite3.connect(":memory:") 
conn.execute("CREATE TABLE person(firstname,lastname)") 
conn.executemany("INSERT INTO person(firstname,lastname) VALUES(?,?)",persons) 
for row in conn.execute("SELECT firstname,lastname FROM person"): 
  print(row) 
   
print("I just deleted",conn.execute("DELETE FROM person").rowcount,"rows")

y ========
('Jim', 'Green')
('Hu', 'jie')
I just deleted 2 rows