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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 duplicates(inlist):
 """ Returns duplicate items in the FIRST dimension of the passed list. Usage: duplicates (inlist) """

    dups = []
    for i in range(len(inlist)):
        if inlist[i] in inlist[i+1:]:
            dups.append(inlist[i])
    return dups