julia> (Dict{NTuple{L, <:Integer}, <:Real} where L) == Dict{NTuple{L, I} where I<:Integer, <:Real} where L
true

Thus, the first type on the RHS accepts dicts whose key type is literally NTuple{L, I} where I<:Integer (but not any subtype thereof because of default invariance) and whose element type is any subtype of Real.