attributes hash assumes symbols, fails with strings, pretty dumb

[mustmodify]

class Fu < Valuable
  has_value :bar
end

>> f = Fu.new(bar: 6)

>> f.attributes['bar']
=> nil

>> f.attributes[:bar]
=> 6

[mustmodify]

Well, in order to get this to work, we'd need something like HashWithIndifferentAccess. Alternately, we could make this work for JUST attributes but not, for example, f.attributes['fu']['bar']. So ... 🤷‍♂