code: def mongo_conn(request):
      global c
      try:
          from pymongo import MongoClient
      except ImportError:
          pytest.skip("Requires mongodb")
  
      conn_kwargs = {}
      if "DB_IP" in os.environ:
          conn_kwargs["host"] = os.environ["DB_IP"]
      if "DBA_MONGODB_ADMIN_URI" in os.environ:
          # On ShiningPanda, we need a username and password to connect. They are
          # passed in a mongodb:// URI.
          conn_kwargs["host"] = os.environ["DBA_MONGODB_ADMIN_URI"]
      if "DB_PORT" in os.environ:
          conn_kwargs["port"] = int(os.environ["DB_PORT"])
  
      try:
          c = MongoClient(**conn_kwargs)
      except Exception:
          c = None
      if c is not None:
          request.addfinalizer(lambda: c.drop_database("iptestdb"))
      return c
  
file_path: ipyparallel/ipyparallel/tests/test_mongodb.py
imports: import os
  from unittest import TestCase
  import pytest
  from .None import test_db
label_desc: Use image node_id 1 for calling a global function with example usage: mongo_conn(request) and returns: c