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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 insort_no_dup(lst, item):
 """ If item is not in lst, add item to list at its sorted position """

    import bisect
    ix = bisect.bisect_left(lst, item)
    if lst[ix] != item: 
        lst[ix:ix] = [item]