text: import json
  import os
  
  CONFIG_FILE = os.environ.get("CONFIG_FILE", "config/dev.json")
  
  try: 
      with open(CONFIG_FILE, 'r') as json_data_file:
          cfg = json.load(json_data_file)
  except FileNotFoundError:
      print("Could not find config file '{}'".format(CONFIG_FILE))
      cfg = {}
  
  for key in ["DB_USERNAME", "DB_PASSWORD", "DB_HOST_URL"]:
      if key not in cfg:
          cfg[key] = None
      cfg[key] = os.environ.get(key, cfg[key])
  