use ansible_facts in module code

I am trying to create my own ansible module (which will update cmdb) and i am looking how to use ansible_facts in module code ?

example of my module script is :

#!/usr/bin/python

from ansible.module_utils.basic import *

import json, ast

from servicenow import ServiceNow
from servicenow import Connection


def __get_server_info(table,server_name="", sys_id=""):
     if sys_id == "":
       return table.fetch_one({'name': server_name})

     if server_name == "":
       return table.fetch_one({'sys_id': sys_id})

def __update_cmdb_hwinfo(table, sys_id, server_name=""):
    return table.update({'sys_id': sys_id,{'hw_ram': 'Here for example i want to put ansible_facts about server ram size'})


def main():


    fields = {
       "snow_instance": {"required": True, "type": "str"},
       "snow_username": {"required": True, "type": "str"},
       "snow_password": {"required": True, "type": "str"},
       "server_name":   {"required": True, "type": "str" },
       "api_type":      {"default": "JSONv2", "type": "str"},
    }

    module = AnsibleModule(argument_spec=fields)
    snow_connection = Connection.Auth(username=module.params['snow_username'], password=module.params['snow_password'], instance=module.params['snow_instance'], api=module.params['api_typ
e'])
    server = ServiceNow.Base(snow_connection)
    server.__table__ = 'cmdb_ci_server_list.do'

    machine = __get_server_info(server, )
    ## Define connection object to ServiceNow instance
    module.exit_json(changed=False, meta=module.params, msg=machine)


if __name__ == '__main__':
    main()

What variable i should use to call ansible_facts in module script? (And is it even possible? ).