连接字符串中的参考/查找密码

Question

如何在不输入真实密码的情况下在连接详细信息中引用密码？

PWD = '1234'

try:
     con = psycopg2.connect("dbname = 'testdb' user = 'testuser' host = 
      'localhost' password = pwd")
 except:
       print ('I am unable to connect the database')

这不允许我连接，但以下内容将

：

try:
     con = psycopg2.connect("dbname = 'testdb' user = 'testuser' host = 
      'localhost' password = '1234'")
 except:
       print ('I am unable to connect the database')