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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 indexOf(self, item, isSorted=False):
 """ Return the position of the first occurrence of an item in an array, or -1 if the item is not included in the array. """

        array = self.obj
        ret = -1

        if not (self._clean.isList() or self._clean.isTuple()):
            return self._wrap(-1)

        if isSorted:
            i = _.sortedIndex(array, item)
            ret = i if array[i] is item else -1
        else:
            i = 0
            l = len(array)
            while i < l:
                if array[i] is item:
                    return self._wrap(i)
                i += 1
        return self._wrap(ret)