code: def test_legmulx(self):
      assert_equal(leg.legmulx([0]), [0])
      assert_equal(leg.legmulx([1]), [0, 1])
      for i in range(1, 5):
          tmp = 2 * i + 1
          ser = [0] * i + [1]
          tgt = [0] * (i - 1) + [i / tmp, 0, (i + 1) / tmp]
          assert_equal(leg.legmulx(ser), tgt)
  
imports: from functools import reduce
  import numpy
  import numpy.polynomial.legendre
  from numpy.polynomial.polynomial import polyval
  from numpy.testing import assert_almost_equal, assert_raises, assert_equal, assert_
label_desc: Use image node_id 3 for calling the TestArithmetic obj's underlying member method code with example usage: obj.test_legmulx() without return types