code: def test_simplex():
      check_vector_transform(tr.simplex, Simplex(2))
      check_vector_transform(tr.simplex, Simplex(4))
  
      check_transform(
          tr.simplex,
          MultiSimplex(3, 2),
          constructor=pt.matrix,
          test=floatX(np.zeros((2, 2))),
      )
  
imports: import numpy
  import pytensor
  import pytensor.tensor
  import pytest
  from numpy.testing import assert_allclose, assert_array_equal
  from pytensor.tensor.variable import TensorConstant
  import pymc
  import pymc.distributions.transforms
  from pymc.logprob.basic import transformed_conditional_logp
  from pymc.logprob.transforms import Transform
  from pymc.pytensorf import floatX, jacobian
  from pymc.testing import Circ, MultiSimplex, R, Rminusbig, Rplusbig, Simplex, SortedVector, Unit, UnitSortedVector, Vector
label_desc: Use image node_id 5 for calling a global function with example usage: test_simplex() without return types