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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 read_since_ids(users):
 """ Read max ids of the last downloads :param users: A list of users Return a dictionary mapping users to ids """

    since_ids = {}
    for user in users:
        if config.has_option(SECTIONS['INCREMENTS'], user):
            since_ids[user] = config.getint(SECTIONS['INCREMENTS'], user) + 1
    return since_ids