Updated API version + Python 2 version of https://stackoverflow.com/a/34469893/2265500

backup.python2.py

import os
import errno
from subprocess import call
from gitlab import Gitlab

def mkdir_p(path):
    try:
        os.makedirs(path)
    except OSError as exc:  # Python >2.5
        if exc.errno == errno.EEXIST and os.path.isdir(path):
            pass
        else:
            raise

# Register a connection to a gitlab instance, using its URL and a user private token
gl = Gitlab('http://gitlab.example.com', 'dasidIOsOJISI092812ihas')
groupsToSkip = ['youDontWantThisGroup']

gl.auth() # Connect to get the current user

gitBasePathRelative = "git/"
gitBasePathRelativeAbsolut = os.path.expanduser("~/" + gitBasePathRelative)
mkdir_p(gitBasePathRelativeAbsolut)

for p in gl.projects.list(all=True):
    if not any(p.namespace.path in s for s in groupsToSkip):
        pathToFolder = gitBasePathRelative + p.namespace.name + "/" + p.name
        commandArray = ["mr", "config", pathToFolder, "checkout=git clone '" + p.ssh_url_to_repo + "' '" + p.name + "'"]
        call(commandArray)

os.chdir(gitBasePathRelativeAbsolut)

call(["mr", "update"])

backup.python3.py

import os
from subprocess import call
from gitlab import Gitlab

# Register a connection to a gitlab instance, using its URL and a user private token
gl = Gitlab('http://gitlab.example.com', 'dasidIOsOJISI092812ihas')
groupsToSkip = ['youDontWantThisGroup']

gl.auth() # Connect to get the current user

gitBasePathRelative = "git/"
gitBasePathRelativeAbsolut = os.path.expanduser("~/" + gitBasePathRelative)
os.makedirs(gitBasePathRelativeAbsolut,exist_ok=True)

for p in gl.projects.list(all=True):
    if not any(p.namespace.path in s for s in groupsToSkip):
        pathToFolder = gitBasePathRelative + p.namespace.name + "/" + p.name
        commandArray = ["mr", "config", pathToFolder, "checkout=git clone '" + p.ssh_url_to_repo + "' '" + p.name + "'"]
        call(commandArray)

os.chdir(gitBasePathRelativeAbsolut)

call(["mr", "update"])