code: def testAdagrad(self):
      def loss(xs):
          x1, x2 = xs
          return jnp.sum(x1**2) + jnp.sum(x2**2)
  
      num_iters = 100
      step_size = 0.1
      x0 = (jnp.ones(2), jnp.ones((2, 2)))
      self._CheckOptimizer(
          optimizers.adagrad, loss, x0, num_iters, step_size
      )
  
imports: import functools
  from absl.testing import absltest
  import numpy
  import jax.numpy
  import jax._src.test_util
  from jax import jit, grad, jacfwd, jacrev
  from jax import tree_util
  from jax import lax
  from jax.example_libraries import optimizers
  from jax import config
label_desc: Use image node_id 12 for calling the OptimizerTests obj's underlying member method code with example usage: obj.testAdagrad() and returns: unknown