class_docstr: A `tf.linalg.LinearOperator` representing a kernel covariance matrix.
class_docstr_tok: ["A","`","tf.linalg.LinearOperator","`","representing","a","kernel","covariance","matrix","."]
code: def _x1_x2_axis_kernel(self):
      x1, x2 = self._x1_x2()
      kernel = self._kernel()
      return x1, x2, -kernel.feature_ndims - 1, kernel
  
imports: import functools
  import tensorflow.compat.v1
  import tensorflow.compat.v2
  from tensorflow_probability.python.internal import dtype_util
  from tensorflow_probability.python.internal import prefer_static
  from tensorflow_probability.python.internal import tensor_util
  from tensorflow.python.ops import control_flow_util
label_desc: Use image node_id 8 for calling the LinearOperatorPSDKernel obj's underlying member method code with example usage: obj._x1_x2_axis_kernel() and returns: x1,  x2,  unknown,  kernel