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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 list_milestones(page_size=200, page_index=0, q="", sort=""):
 """ List all ProductMilestones """

    data = list_milestones_raw(page_size, page_index, sort, q)
    if data:
        return utils.format_json_list(data)