def _get_exploration_memcache_key(exploration_id, version=None):
 if version:
  return ('exploration-version:%s:%s' % (exploration_id, version))
 else:
  return ('exploration:%s' % exploration_id)

def _get_exploration_memcache_key ( exploration_id , version = None ) : if version : return ( 'exploration-version:%s:%s' % ( exploration_id , version ) ) else : return ( 'exploration:%s' % exploration_id )
returns a memcache key for an exploration .