Return the position of the first occurrence of an
        item in an array, or -1 if the item is not included in the array.

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)