"""
    copy(t::AbstractDataTask)

Fallback implementation of the copy of an abstract data task, throwing an error.
"""
copy(t::AbstractDataTask) = error("Need to implement copying for your data tasks!")

"""
    copy(t::AbstractComputeTask)

Return a copy of the given compute task.
"""
copy(t::AbstractComputeTask) = typeof(t)()

"""
    copy(t::FusedComputeTask)

Return a copy of th egiven [`FusedComputeTask`](@ref).
"""
function copy(t::FusedComputeTask{T1, T2}) where {T1, T2}
    return FusedComputeTask{T1, T2}(
        copy(t.first_task),
        copy(t.second_task),
        copy(t.t1_inputs),
        t.t1_output,
        copy(t.t2_inputs),
    )
end

FusedComputeTask{T1, T2}(t1_inputs::Vector{String}, t1_output::String, t2_inputs::Vector{String}) where {T1, T2} =
    FusedComputeTask{T1, T2}(T1(), T2(), t1_inputs, t1_output, t2_inputs)