code: def test_basic(self):
      # Standard distributions
      rv = pm.Normal.dist(mu=2.3)
      np.testing.assert_allclose(moment(rv).eval(), 2.3)
  
      # Special distributions
      rv = pm.Flat.dist()
      assert moment(rv).eval() == np.zeros(())
      rv = pm.HalfFlat.dist()
      assert moment(rv).eval() == np.ones(())
      rv = pm.Flat.dist(size=(2, 4))
      assert np.all(moment(rv).eval() == np.zeros((2, 4)))
      rv = pm.HalfFlat.dist(size=(2, 4))
      assert np.all(moment(rv).eval() == np.ones((2, 4)))
  
imports: import cloudpickle
  import numpy
  import pytensor
  import pytensor.tensor
  import pytest
  from pytensor.tensor.random.op import RandomVariable
  import pymc
  from pymc.distributions.distribution import moment
  from pymc.initial_point import make_initial_point_fn, make_initial_point_fns_per_chain
label_desc: Use image node_id 1 for calling the TestMoment obj's underlying member method code with example usage: obj.test_basic() without return types