Fix export warning

Author: YingboMa

src/bipartite_graph.jl

@@ -2,14 +2,13 @@ module BipartiteGraphs
 
 export BipartiteEdge, BipartiteGraph
 
-using Reexport
 export 𝑠vertices, 𝑑vertices, has_𝑠vertex, has_𝑑vertex, 𝑠neighbors, 𝑑neighbors,
        𝑠edges, 𝑑edges, nsrcs, ndsts, SRC, DST
 
 using DocStringExtensions
 using UnPack
 using SparseArrays
-@reexport using LightGraphs
+using LightGraphs
 using Setfield
 
 ###

src/structural_transformation/StructuralTransformations.jl

@@ -21,6 +21,7 @@ using ModelingToolkit: ODESystem, AbstractSystem, var_from_nested_derivative,
                        ExtraVariablesSystemException
 
 using ModelingToolkit.BipartiteGraphs
+using LightGraphs
 using ModelingToolkit.SystemStructures
 
 using ModelingToolkit.DiffEqBase

src/systems/systemstructure.jl

@@ -6,6 +6,7 @@ using ..ModelingToolkit
 import ..ModelingToolkit: isdiffeq, var_from_nested_derivative, vars!, flatten,
     value, InvalidSystemException, isdifferential, _iszero, isparameter
 using ..BipartiteGraphs
+using LightGraphs
 using UnPack
 using Setfield
 using SparseArrays