Get value of column corresponding to condition being met for another column in a Grouped DataFrame

New to Julia
,
1 
using DataFrames, DataFramesMeta
df = DataFrame(x = [1,1,1,2,2,2], y = [1,2,3,101,102,103], z = [5, 6, 7, 505, 506, 507])
gdf = groupby(df, :x)
@combine(gdf, :MaxY = maximum(:y))

Above is MWE. I group by x column and find the max of y column and need the corresponding value of z being returned for each group’s max y value.

I am not sure how to get the corresponding z value? Help appreciated

2 
julia> @combine(gdf, :Maxz = :z[argmax(:y)])
2×2 DataFrame
 Row │ x      Maxz
     │ Int64  Int64
─────┼──────────────
   1 │     1      7
   2 │     2    507

(assuming that you have a unique maximum value)

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