def unique_days_of_one_stream(input_dict: dict) -> set:
    """
    This function takes a dictionary of stream ids with dates of each stream
    and makes a unique set of dates for all the stream ids

    :param dict input_dict: a dictionary of stream ids as keys with dates as values
    :return: a set of dates for all the stream ids of one stream for a day
    :rtype: set
    """
    merged_dates = []

    for stream_id in input_dict:
        merged_dates = list(set(merged_dates + input_dict[stream_id]))

    merged_dates_set = set(merged_dates)
    return merged_dates_set