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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def convert_values(args_list):
 """convert_value in bulk. :param args_list: list of value, source, target currency pairs :return: map of converted values """

    rate_map = get_rates(map(itemgetter(1, 2), args_list))
    value_map = {}
    for value, source, target in args_list:
        args = (value, source, target)
        if source == target:
            value_map[args] = value
        else:
            value_map[args] = value * rate_map[(source, target)]

    return value_map