Position strategy or sub-portfolio tagging

I’d like to suggest adding an attribute or two to allow for strategy tagging and/or denoting a sub-portfolio on the Position object. Perhaps this could be updated with a POST?

{
    "asset_id": "c1f59ac6-1836-416a-9837-5fa3b1d1da9b",
    "symbol": "BNKU",
    "exchange": "ARCA",
    "asset_class": "us_equity",
    "asset_marginable": false,
    "qty": "120",
    "avg_entry_price": "34.69",
    "side": "long",
    "market_value": "4340.4",
    "cost_basis": "4162.8",
    "unrealized_pl": "177.6",
    "unrealized_plpc": "0.0426635918132027",
    "unrealized_intraday_pl": "2.4",
    "unrealized_intraday_plpc": "0.0005532503457815",
    "current_price": "36.17",
    "lastday_price": "36.15",
    "change_today": "0.0005532503457815",
    "qty_available": "0"
},