Returned Dictionaries.Dictonary type does not adhere to Julia Dict interface

I was expecting to be able to iterate through these grouped dictionaries, but I'm noticing they do not seem to follow the AbstractDict interface. Is this an intentional design decision? If so, is there a benefit to this counterintuitive behavior?

julia> group(iseven, 1:5)
2-element Dictionaries.Dictionary{Bool, Vector{Int64}}
 false │ [1, 3, 5]
  true │ [2, 4]

julia> Dict(false => [1, 3, 5], true => [2, 4])
Dict{Bool, Vector{Int64}} with 2 entries:
  0 => [1, 3, 5]
  1 => [2, 4]

julia> collect(group(iseven, 1:5))
2-element Vector{Vector{Int64}}:
 [1, 3, 5]
 [2, 4]

julia> collect(Dict(false => [1, 3, 5], true => [2, 4]))
2-element Vector{Pair{Bool, Vector{Int64}}}:
 0 => [1, 3, 5]
 1 => [2, 4]

Start by reproducing the grouped-dictionary iteration examples in Julia and compare them with the AbstractDict and Dict interfaces. Determine the intended iteration behavior and document a concrete acceptance criterion before identifying the relevant implementation and tests; done means the behavior is agreed and covered by regression tests.