docs: def avail_sizes(call=None):
      '''
      Return a dict of all available VM sizes on the cloud provider with
      relevant data.
      '''
      if call == 'action':
          raise SaltCloudSystemExit(
              'The avail_sizes function must be called with '
              '-f or --function, or with the --list-sizes option'
          )
  
      conn = get_conn()
  
      sizes = conn.fixed_server_flavors()
  
      return sizes