code: def test_chebpow(self):
      for i in range(5):
          for j in range(5):
              msg = f"At i={i}, j={j}"
              c = np.arange(i + 1)
              tgt = reduce(cheb.chebmul, [c] * j, np.array([1]))
              res = cheb.chebpow(c, j)
              assert_equal(trim(res), trim(tgt), err_msg=msg)
  
imports: from functools import reduce
  import numpy
  import numpy.polynomial.chebyshev
  from numpy.polynomial.polynomial import polyval
  from numpy.testing import assert_almost_equal, assert_raises, assert_equal, assert_
label_desc: Use image node_id 6 for calling the TestArithmetic obj's underlying member method code with example usage: obj.test_chebpow() without return types