#!/usr/bin/python3

import psycopg2

db = psycopg2.connect("dbname=test")

cur = db.cursor()

_name = "fred'; delete from students; select '";

q1 = f"select * from students where name = '{_name}'"
q2 = "select * from students where name = %s"

print(cur.mogrify(q1))
print(cur.mogrify(q2,[_name]))