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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 mean_date(dt_list):
 """Calcuate mean datetime from datetime list """

    dt_list_sort = sorted(dt_list)
    dt_list_sort_rel = [dt - dt_list_sort[0] for dt in dt_list_sort]
    avg_timedelta = sum(dt_list_sort_rel, timedelta())/len(dt_list_sort_rel)
    return dt_list_sort[0] + avg_timedelta