def update_strategy(strat1, strat2):
    """
    Updates strategy 1 by adding key/value pairs of strategy 2.
    :param strat1: Old strategy.
    :param strat2: Strategy to add.
    :return: A new strategy which merges strategies 1 and 2 (2 overwrites 1 in case of duplicate keys)
    """
    new_strat = strat1.copy()
    new_strat.update(strat2)
    return new_strat