function _burn(uint _tokenId) internal {
    require(_isApprovedOrOwner(msg.sender, _tokenId), "caller is not owner nor approved");

    address owner = ownerOf(_tokenId);

    // Clear approval
    approve(address(0), _tokenId);
    // TODO add delegates
    // Remove token
    _removeTokenFrom(msg.sender, _tokenId);
    emit Transfer(owner, address(0), _tokenId);
}
// All the same plus _tokenId
require(
    dstRepOld.length + 1 <= MAX_DELEGATES,
    "dstRep would have too many tokenIds"
);
function _burn(uint _tokenId) internal {
    require(_isApprovedOrOwner(msg.sender, _tokenId), "caller is not owner nor approved");

    address owner = ownerOf(_tokenId);

    // Clear approval
    approve(address(0), _tokenId);
    // remove delegates
    _moveTokenDelegates(delegates(_to), address(0), _tokenId);
    // Remove token
    _removeTokenFrom(msg.sender, _tokenId);
    emit Transfer(owner, address(0), _tokenId);
}
