Docs: improve sqlite3 placeholders example (GH-101092)

(cherry picked from commit b84be8d9c0)

Co-authored-by: Erlend E. Aasland <erlend.aasland@protonmail.com>

Doc/library/sqlite3.rst

@@ -1841,19 +1841,18 @@ Here's an example of both styles:
    con = sqlite3.connect(":memory:")
    cur = con.execute("CREATE TABLE lang(name, first_appeared)")
 
-   # This is the qmark style:
+   # This is the named style used with executemany():
-   cur.execute("INSERT INTO lang VALUES(?, ?)", ("C", 1972))
+   data = (
+       {"name": "C", "year": 1972},
+       {"name": "Fortran", "year": 1957},
+       {"name": "Python", "year": 1991},
+       {"name": "Go", "year": 2009},
+   )
+   cur.executemany("INSERT INTO lang VALUES(:name, :year)", data)
 
-   # The qmark style used with executemany():
+   # This is the qmark style used in a SELECT query:
-   lang_list = [
+   params = (1972,)
-       ("Fortran", 1957),
+   cur.execute("SELECT * FROM lang WHERE first_appeared = ?", params)
-       ("Python", 1991),
-       ("Go", 2009),
-   ]
-   cur.executemany("INSERT INTO lang VALUES(?, ?)", lang_list)
-
-   # And this is the named style:
-   cur.execute("SELECT * FROM lang WHERE first_appeared = :year", {"year": 1972})
    print(cur.fetchall())
 
 .. testoutput::