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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 _refine_upcheck(merge, min_goodness):
 """Remove from the merge any entries which would be covered by entries between their current position and the merge insertion position. For example, the third entry of:: 0011 -> N 0100 -> N 1000 -> N X000 -> NE Cannot be merged with the first two entries because that would generate the new entry ``XXXX`` which would move ``1000`` below the entry with the key-mask pair of ``X000``, which would cover it. Returns ------- :py:class:`~.Merge` New merge with entries possibly removed. If the goodness of the merge ever drops below `min_goodness` then an empty merge will be returned. bool If the merge has been changed at all. """

    # Remove any entries which would be covered by entries above the merge
    # position.
    changed = False
    for i in sorted(merge.entries, reverse=True):
        # Get all the entries that are between the entry we're looking at the
        # insertion index of the proposed merged index. If this entry would be
        # covered up by any of them then we remove it from the merge.
        entry = merge.routing_table[i]
        key, mask = entry.key, entry.mask
        if any(intersect(key, mask, other.key, other.mask) for other in
               merge.routing_table[i+1:merge.insertion_index]):
            # The entry would be partially or wholly covered by another entry,
            # remove it from the merge and return a new merge.
            merge = _Merge(merge.routing_table, merge.entries - {i})
            changed = True

            # Check if the merge is sufficiently good
            if merge.goodness <= min_goodness:
                merge = _Merge(merge.routing_table)  # Replace with empty merge
                break

    # Return the final merge
    return merge, changed