Symbolics.jl not threadsafe?

Question

I am trying to use Symbolics.jl to perform parallel symbolic manipulations, but it seems like the package is not threadsafe.

With the following code,

Threads.@threads for i in range(1,8)
    @variables k
    expand(k)
    println(i)
end

I get the following error

ERROR: LoadError: TaskFailedException
Stacktrace:
 [1] wait
   @ ./task.jl:345 [inlined]
 [2] threading_run(fun::var"#3#threadsfor_fun#2"{var"#3#threadsfor_fun#1#3"{UnitRange{Int64}}}, static::Bool)
   @ Base.Threads ./threadingconstructs.jl:38
 [3] top-level scope
   @ ./threadingconstructs.jl:89
8
    nested task error: 
One of x or y already in this Bijection
    Stacktrace:
      [1] error(s::String)
        @ Base ./error.jl:35
      [2] setindex!(b::Bijections.Bijection{Any, Any}, y::SymbolicUtils.Sym{Real, Base.ImmutableDict{DataType, Any}}, x::DynamicPolynomials.PolyVar{true})
        @ Bijections ~/.julia/packages/Bijections/IWrOY/src/Bijections.jl:74
      [3] polyize(x::SymbolicUtils.Sym{Real, Base.ImmutableDict{DataType, Any}}, pvar2sym::Bijections.Bijection{Any, Any}, sym2term::Dict{SymbolicUtils.Sym, Any}, vtype::Type, pow::Function, Fs::Type, recurse::Bool)
        @ SymbolicUtils ~/.julia/packages/SymbolicUtils/qulQp/src/polyform.jl:178
      [4] PolyForm(x::SymbolicUtils.Sym{Real, Base.ImmutableDict{DataType, Any}}, pvar2sym::Bijections.Bijection{Any, Any}, sym2term::Dict{SymbolicUtils.Sym, Any}, vtype::Type; Fs::Type, recurse::Bool, metadata::Base.ImmutableDict{DataType, Any})
        @ SymbolicUtils ~/.julia/packages/SymbolicUtils/qulQp/src/polyform.jl:196
      [5] expand(expr::SymbolicUtils.Sym{Real, Base.ImmutableDict{DataType, Any}})
        @ SymbolicUtils ~/.julia/packages/SymbolicUtils/qulQp/src/polyform.jl:262
      [6] expand(n::Num)
        @ Symbolics ~/.julia/packages/Symbolics/FGTCH/src/Symbolics.jl:154
      [7] macro expansion
        @ ~/Documents/cmb_replication/test_example.jl:6 [inlined]
      [8] (::var"#3#threadsfor_fun#2"{var"#3#threadsfor_fun#1#3"{UnitRange{Int64}}})(tid::Int64; onethread::Bool)
        @ Main ./threadingconstructs.jl:84
      [9] #3#threadsfor_fun
        @ ./threadingconstructs.jl:51 [inlined]
     [10] (::Base.Threads.var"#1#2"{var"#3#threadsfor_fun#2"{var"#3#threadsfor_fun#1#3"{UnitRange{Int64}}}, Int64})()
        @ Base.Threads ./threadingconstructs.jl:307

Is there anyway to use locks or other thread-safe tools with Symbolics.jl to allow for parallel computation with this package?