code: def test_basic(self):
      c = np.array([0, 1, -2, 3])
      v = vander(c)
      powers = np.array(
          [
              [0, 0, 0, 0, 1],
              [1, 1, 1, 1, 1],
              [16, -8, 4, -2, 1],
              [81, 27, 9, 3, 1],
          ]
      )
      # Check default value of N:
      assert_array_equal(v, powers[:, 1:])
      # Check a range of N values, including 0 and 5 (greater than default)
      m = powers.shape[1]
      for n in range(6):
          v = vander(c, N=n)
          assert_array_equal(v, powers[:, m - n : m])
  
imports: from numpy.testing import assert_equal, assert_array_equal, assert_array_max_ulp, assert_array_almost_equal, assert_raises, assert_
  from numpy import arange, add, fliplr, flipud, zeros, ones, eye, array, diag, histogram2d, tri, mask_indices, triu_indices, triu_indices_from, tril_indices, tril_indices_from, vander
  import numpy
  import pytest
label_desc: Use image node_id 1 for calling the TestVander obj's underlying member method code with example usage: obj.test_basic() without return types