code: def mongo_host(arctic):
      return arctic.mongo_host
  
imports: import getpass
  import os
  import random
  import string
  import unittest
  import numpy
  import pandas
  import pytest
  from pandas.tseries.offsets import Day
  from past.utils import old_div
  from six import PY3
label_desc: Use image node_id 5 for calling a global function with example usage: mongo_host(arctic) and returns: arctic