docs: def main():
      '''main routine'''
      # Load Azure app defaults
      try:
          with open('azurermconfig.json') as config_file:
              config_data = json.load(config_file)
      except FileNotFoundError:
          sys.exit('Error: Expecting azurermconfig.json in current folder')
  
      tenant_id = config_data['tenantId']
      app_id = config_data['appId']
      app_secret = config_data['appSecret']
      subscription_id = config_data['subscriptionId']
  
      access_token = azurerm.get_access_token(tenant_id, app_id, app_secret)
  
      # list storage accounts per sub
      sa_list = azurerm.list_storage_accounts_sub(access_token, subscription_id)
      # print(sa_list)
      for sta in sa_list['value']:
          print(sta['name'] + ', ' + sta['properties']['primaryLocation'] + ', '
                + rgfromid(sta['id']))
  
      # get storage account quota
      quota_info = azurerm.get_storage_usage(access_token, subscription_id)
      used = quota_info['value'][0]['currentValue']
      limit = quota_info["value"][0]["limit"]
      print('\nUsing ' + str(used) + ' accounts out of ' + str(limit) + '.')