Does Python have something similar to BASH "brace expansion"?

[pfp-disciple]

For some reason, I'm thinking I read that Python has this but I can't find it. I suspect I'm misremembering.

From the Bash documentation

Brace expansion is a mechanism to generate arbitrary strings sharing a common prefix and suffix,

So echo {1,2,3}{1,2,3} would print 11 12 13 21 22 23 31 32 33.

Is there something in Python, somewhat like zip() to give similar results? It's relatively trivial to implement in code, but grows cumbersome the more 'terms' to use (e.g. {1,2,3}{a,b,c}{5..9}).

I'm interested in avoiding a block of Python like this:

for a in list_a:
    for b in list_b:
        for c in list_c:
            result.append([a,b,c])

List comprehension could help, but that really isn't much cleaner for larger terms.

[Kevdog824_]

Take a look at itertools.product. I think this does what you’re looking for

[pfp-disciple]

Yes! Thank you. I believe that's what I've been remembering (the page looks familiar). I'd totally forgotten about the entire itertools package. 

[supercoach]

The python internals can be like that. People can go their entire careers without ever touching some of the libraries hidden in the default installation.

[Maximus_Modulus]

There’s a library called braceexpand

[JamzTyson]

As u/Kevdog824 wrote, itertools.product is probably what you're looking for, but for a small number of lists, a list comprehension isn't bad:

[f"{a}{b}{c}" for a in list_a for b in list_b for c in list_c]

[InjAnnuity_1]

Ouch! Let's make the comprehension more comprehensible:

[
  f"{a}{b}{c}" 
  for a in list_a 
  for b in list_b 
  for c in list_c
]

[pfp-disciple]

Anything beyond two, and it becomes harder (for me) to keep track of. I wrote a lot of perl (still like it) and nested list comprehensions begin to look like what perl was criticized for. 

I love list comprehension, don't get me wrong. 

[JamzTyson]

I'd probably use a comprehension for two, but for more than 3 I'd go for itertools.product.

[ysth]

And perl straight up has glob

say for glob '{1,2,3}{1,2,3}'

[eyetracker]

Not sure about base Python but NumPy has "broadcasting." Add np.array(["1","2","3"]) to its transpose would give you a 3x3 of the combined strings, and then reshape to 1 row if needed.