python正则表达式对象在字典中是否可以迭代循环？

Question

所以我试图在python中包含正则表达式对象的字典上运行for循环，但是我收到以下错误：

============ RESTART: C:/Users/JSurzyn/Scripts/pw_verify_neat.py ============
Enter a password >>>
Jordan93
Traceback (most recent call last):
  File "C:/Users/JSurzyn/Scripts/pw_verify_neat.py", line 18, in <module>
    for key, value in reg_dict:
TypeError: '_sre.SRE_Pattern' object is not iterable

正则表达式对象是否不可迭代？任何帮助都会很棒。我在Windows 10 64位计算机上运行python 3.6。

上下文。我正在尝试使用以下代码

import re

pw = str(input('Enter a password >>>\n' ))

length_regex = re.compile(r'.{8,}')
upper_regex = re.compile(r'[A-Z]')
lower_regex = re.compile(r'[a-z]')
num_regex = re.compile(r'[0-9]')

def t_pw(pw):
    try:
        mo = length_regex.search(pw)
        fo = mo.group()
        try:
            mo = upper_regex.search(pw)
            fo = mo.group()
            try:
                mo = lower_regex.search(pw)
                fo = mo.group()
                try:
                    mo = num_regex.search(pw)
                    fo = mo.group()
                    print('password approved')
                except:
                    print('password must have at least one numerical digit')
            except:
                print('password must have at least one lower case letter')
        except:
            print('password must have at least one upper case letter')

    except:
        print('password must be at least 8 characters.')


t_pw(pw)

并清理它看起来像：

import re

pw = str(input('Enter a password >>>\n' ))

length_regex = re.compile(r'.{8,}')
upper_regex = re.compile(r'[A-Z]')
lower_regex = re.compile(r'[a-z]')
num_regex = re.compile(r'[0-9]')

l_string = 'password must be at least 8 characters.'
u_string = 'password must have at least one upper case letter'
lo_string = 'password must have at least one lower case letter'
n_string = 'password must have at least one numerical digit'

reg_dict = {length_regex : l_string, upper_regex : u_string,
            lower_regex : lo_string, num_regex : n_string}

for key, value in reg_dict:
    try:
        mo = key.search(pw)
        fo = mo.group()
    except:
        print(value)
        exit()

print('Password approved')