code: def test_multivariate_polynomial_basis():
      np.random.seed(1)
      x = np.random.normal(0, 1, (10, 2))
      degrees = [3, 4]
      mps = PolynomialSmoother(x, degrees)
      for i, deg in enumerate(degrees):
          uv_basis = UnivariatePolynomialSmoother(
              x[:, i], degree=deg
          ).basis
          assert_allclose(mps.smoothers[i].basis, uv_basis)
  
imports: import pytest
  import numpy
  from numpy.testing import assert_allclose, assert_equal
  from statsmodels.gam.smooth_basis import UnivariatePolynomialSmoother, PolynomialSmoother, BSplines
label_desc: Use image node_id 2 for calling a global function with example usage: test_multivariate_polynomial_basis() without return types