Search through the string's space for find the target string whose md5sum matches the required condition.

[Hongyi Zhao <hongyi.zhao@gmail.com>]

Suppose we have a string represented as follows, where `?' represents
arbitrary uppercase letters:

TASC?O3RJMV?WDJKX?ZM

We also know that its md5sum has the following form:

E903???4DAB????08?????51?80??8A?

Based on the above information, find out the string and its
corresponding md5sum.

I've done the work with the following python code:

```python
import re
from hashlib import md5
from string import ascii_uppercase

alphabet_uppercase=ascii_uppercase
re_md5_str=re.compile(r'^E903[A-F0-9]{3}4DAB[A-F0-9]{4}08[A-F0-9]{5}51[A-F0-9]80[A-F0-9]{2}8A[A-F0-9]')

#result_str=[]
for i in alphabet_uppercase:
    i_str= 'TASC' + i
    for j in alphabet_uppercase:
        j_str = i_str + 'O3RJMV' + j
        for k in alphabet_uppercase:
            k_str = j_str + 'WDJKX' + k + 'ZM'
            #result_str.append(k_str)
            md5_str=md5(k_str.encode('utf-8')).hexdigest().upper()
            if re_md5_str.match(md5_str):
                md5_str = re_md5_str.match(md5_str)[0]
                print('The string: ' + k_str + '\n' + 'md5sum: ' + md5_str)
```

But I would like to know the ELISP implementation for the above
question. Any hints will be greatly appreciated.

Regards, HZ