Error in Flux v0.10.0 tutorial

I’m trying the Flux tutorial https://fluxml.ai/Flux.jl/stable/models/basics/ and got weird error:

using Flux
W = rand(2, 5)
b = rand(2)
predict(x) = W*x .+ bfunction loss(x, y)
ŷ = predict(x)
sum((y .- ŷ).^2)
endx, y = rand(5), rand(2)gs = gradient(() -> loss(x, y), params(W, b))
W̄ = gs[W]

ERROR: KeyError: key [0.6494686402869012 0.16642755891498795 … 0.3477631878161558 0.7117085219963473; 0.924010195090909 0.7238725578121123 … 0.25837956485675106 0.15091689039220757] not found

How to make it return the right thing?

This code works for me (Julia 1.3, Flux 0.10). (After correcting the indentation of course.)