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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 remove_duplicates(items):
 """ Returns a list without duplicates, keeping elements order :param items: A list of items :return: The list without duplicates, in the same order """

    if items is None:
        return items

    new_list = []
    for item in items:
        if item not in new_list:
            new_list.append(item)
    return new_list