assign rank and maintain sequence across duplicates

I'm assigning an incremental rank based on a value, but need to assign the same rank to duplicate values and maintain the overall sequence.

Instead of this:

I need this:

I'm actually doing this in an ArcGIS Pro toolbox script.

So far I've only got this far, which doesn't address the duplicates:

    d = {'value': [500,120,175,400,250,250], 'rank': [0,0,0,0,0,0]
    df = pd.DataFrame(data=d)

    rank1 = df['value']
    rank1 = rank1.sort_values(ascending=False)
    rank1 = rank1.to_numpy()
    rank2 = np.arange(1,len(rank1)+1,1)

rank1: [500 400 250 250 175 120] rank2: [1 2 3 4 5 6]

Desired output is: rank2: [1 2 3 3 5 6]

You can use rank:

df["rank"] = df["value"].rank(method="min", ascending=False).astype(int)

   value  rank
0    500     1
1    120     6
2    175     5
3    400     2
4    250     3
5    250     3