code: func (db *Database) Len() int {
  	db.lock.RLock()
  	defer db.lock.RUnlock()
  
  	return len(db.db)
  }
docs: // Len returns the number of entries currently present in the memory database.
  //
  // Note, this method is only used for testing (i.e. not public in general) and
  // does not have explicit checks for closed-ness to allow simpler testing code.