docs: def load_config():
      """Load configuration file containing API KEY and other settings.
  
      :rtype: str
      """
  
      configfile = get_configfile()
  
      if not os.path.exists(configfile):
          data = {
              'apikey': 'GET KEY AT: https://www.filemail.com/apidoc/ApiKey.aspx'
              }
  
          save_config(data)
  
      with open(configfile, 'rb') as f:
          return json.load(f)