def _format_key(key):
 (schema, table) = key
 table = (table or '(FACT)')
 if schema:
  return '{}.{}'.format(schema, table)
 else:
  return table

def _format_key ( key ) : ( schema , table ) = key table = ( table or '(FACT)' ) if schema : return '{}.{}' . format ( schema , table ) else : return table
format table key key to a string .