code: def test_print_dim_base():
      mksa = DimensionSystem(
          (length, time, mass, current),
          (action,),
          {action: {mass: 1, length: 2, time: -1}},
      )
      L, M, T = symbols("L M T")
      assert mksa.print_dim_base(action) == L**2 * M / T
  
file_path: sympy/sympy/physics/units/tests/test_dimensionsystem.py
imports: from sympy.core.symbol import symbols
  from sympy.matrices.dense import Matrix, eye
  from sympy.physics.units.definitions.dimension_definitions import action, current, length, mass, time, velocity
  from sympy.physics.units.dimensions import DimensionSystem
label_desc: Use image node_id 7 for calling a global function with example usage: test_print_dim_base() without return types