Ansible Python module to list groups in inventory (version 0.2 :D)

#! /bin/python
#Ansible module with Python to list groups in inventory (version 0.2 :D)
#You can print output like "pretty-print" outside Ansible by using:
#./listgroups | python -m json.too

import os
import re
import json

#Get hosts inventory from ansible.cfg file.
ansible_conf_file = open("ansible.cfg").read()
hosts_file = re.findall('^hostfile\s*=\s*(.*)', ansible_conf_file, re.MULTILINE)[0]

#Get data from hostsfile.
hosts_file = open(hosts_file)
groups_and_members = hosts_file.read().splitlines()
hosts_file.close()

#Preste for counting loop.
first_element = 0
number_of_group_members = 0
gropus_list= {}

#Get groups and number of its members from inventory file and add it to dictionary. 
for line in groups_and_members:
  if re.match("^\[", line) and first_element == 0:
    group_name = re.sub(r'[\[\]]', '', line)
    first_element=1

  elif not re.match("(^\[|#|^$)", line) and first_element != 0:
    number_of_group_members += 1

  elif re.match("^\[", line) and first_element != 0:
    gropus_list[group_name] = number_of_group_members
    group_name = re.sub(r'[\[\]]', '', line)
    number_of_group_members = 0

#Print output in json format.
print '{"Inventory Groups": ' + json.dumps(gropus_list) + '}'

Output example:

• Raw:

{"Inventory Groups": {"Group1": 5, "Group2": 3, "Group3": 7}}

• With python -m json.tool:

{
    "Inventory Groups": {
        "Group1": 5,
        "Group2": 3,
        "Group3": 7,
    }
}