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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 insert(self, loc, item):
 """ Make new MultiIndex inserting new item at location Parameters loc : int item : tuple Must be same length as number of levels in the MultiIndex Returns ------- new_index : Index """

        # Pad the key with empty strings if lower levels of the key
        # aren't specified:
        if not isinstance(item, tuple):
            item = (item, ) + ('', ) * (self.nlevels - 1)
        elif len(item) != self.nlevels:
            raise ValueError('Item must have length equal to number of '
                             'levels.')

        new_levels = []
        new_codes = []
        for k, level, level_codes in zip(item, self.levels, self.codes):
            if k not in level:
                # have to insert into level
                # must insert at end otherwise you have to recompute all the
                # other codes
                lev_loc = len(level)
                level = level.insert(lev_loc, k)
            else:
                lev_loc = level.get_loc(k)

            new_levels.append(level)
            new_codes.append(np.insert(
                ensure_int64(level_codes), loc, lev_loc))

        return MultiIndex(levels=new_levels, codes=new_codes,
                          names=self.names, verify_integrity=False)