regex - How can I debug a regular expression in Python?

Question

Is there a way to debug a regular expression in Python? And I'm not referring to the process of trying and trying till they work :)

Here is how regexes can be debugged in Perl:

use re 'debug';

my $str = "GET http://some-site.com HTTP/1.1";
if($str =~/gets+(S+)/i) {
    print "MATCH:$1
";
}

The code above produces the following output on my computer when ran:

Compiling REx "gets+(S+)"
Final program:
   1: EXACTF  (3)
   3: PLUS (5)
   4:   SPACE (0)
   5: OPEN1 (7)
   7:   PLUS (9)
   8:     NSPACE (0)
   9: CLOSE1 (11)
  11: END (0)
stclass EXACTF  minlen 5
Matching REx "gets+(S+)" against "GET http://some-site.com HTTP/1.1"
Matching stclass EXACTF  against "GET http://some-site.com HTTP/1.1" (33 chars)
   0           |  1:EXACTF (3)
   3        |  3:PLUS(5)
                                  SPACE can match 1 times out of 2147483647...
   4       |  5:  OPEN1(7)
   4       |  7:  PLUS(9)
                                    NSPACE can match 20 times out of 2147483647...
  24       |  9:    CLOSE1(11)
  24       | 11:    END(0)
Match successful!
MATCH:http://some-site.com
Freeing REx: "gets+(S+)"

Answer 1

>>> p = re.compile('.*', re.DEBUG)
max_repeat 0 65535
  any None
>>>                         

regex '|' operator vs separate runs for each sub-expression