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 azurermonfig.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)
      '''
      pubs = azurerm.list_publishers(access_token, subscription_id, 'southeastasia')
      for pub in pubs:
      #    print(json.dumps(pub, sort_keys=False, indent=2, separators=(',', ': ')))
          print(pub['name'])
  
      offers = azurerm.list_offers(access_token, subscription_id, 'southeastasia', 'rancher')
      for offer in offers:
          print(json.dumps(offer, sort_keys=False, indent=2, separators=(',', ': ')))
  
      skus = azurerm.list_skus(access_token, subscription_id, 'southeastasia', 'rancher', 'rancheros')
      for sku in skus:
          print(sku['name'])
      '''
      #print('Versions for CoreOS:')
      # versions = azurerm.list_sku_versions(access_token, subscription_id, 'eastasia', 'CoreOS',
      #                                     'CoreOS', 'Stable')
      versions = azurerm.list_sku_versions(access_token, subscription_id, 'eastus2', 'Canonical',
                                           'UbuntuServer', '16.04-LTS')
      for version in versions:
          print(version['name'])