code: def test_decay(self):
      def decay(_np, y, t, arg1, arg2):
          return -_np.sqrt(t) - y + arg1 - _np.mean((y + arg2) ** 2)
  
      rng = self.rng()
      args = (rng.randn(3), rng.randn(3))
      y0 = rng.randn(3)
      ts = np.linspace(0.1, 0.2, 4)
      tol = 1e-1 if jtu.num_float_bits(np.float64) == 32 else 1e-3
  
      self.check_against_scipy(decay, y0, ts, *args, tol=tol)
  
      integrate = partial(odeint, partial(decay, jnp))
      jtu.check_grads(
          integrate,
          (y0, ts, *args),
          modes=["rev"],
          order=2,
          rtol=tol,
          atol=tol,
      )
  
imports: from functools import partial
  from absl.testing import absltest
  import numpy
  import jax
  from jax._src import test_util
  import jax.numpy
  from jax.experimental.ode import odeint
  from jax.tree_util import tree_map
  import scipy.integrate
  from jax import config
label_desc: Use image node_id 5 for calling the ODETest obj's underlying member method code with example usage: obj.test_decay() and returns: unknown