old_contents: import Numberjack.solvers.Mistral as Mistral
  import Numberjack.solvers.MiniSat as MiniSat
  
  from LinearTest import LinearTest
  from LogicalTest import LogicalTest
  from GlobalsATest import GlobalsATest
  from MiscTest import MiscTest
  from CoreTest import CoreTest
  from SATEncodingTest import SATEncodingTest
  
  LinearTest.solver = Mistral.Solver
  LogicalTest.solver = Mistral.Solver
  MiscTest.solver = Mistral.Solver
  GlobalsATest.solver = Mistral.Solver
  CoreTest.solver = Mistral.Solver
  SATEncodingTest.solver = MiniSat.Solver
  
new_contents: import Numberjack.solvers.Mistral as TestSolver
  # import Numberjack.solvers.CPLEX as TestSolver
  import Numberjack.solvers.MiniSat as MiniSat
  
  from LinearTest import LinearTest
  from LogicalTest import LogicalTest
  from GlobalsATest import GlobalsATest
  from MiscTest import MiscTest
  from CoreTest import CoreTest
  from SATEncodingTest import SATEncodingTest
  
  LinearTest.solver = TestSolver.Solver
  LogicalTest.solver = TestSolver.Solver
  MiscTest.solver = TestSolver.Solver
  GlobalsATest.solver = TestSolver.Solver
  CoreTest.solver = TestSolver.Solver
  SATEncodingTest.solver = MiniSat.Solver
  
subject: make tests/__init__.py script slightly easier to change solver.