Graph visualization failed: GraphDefs failed to reconcile.

In TensorFlow v2, below code can cause GraphDef reconciliation error.

@tf.function
def foo(x):
  return x ** 2

with writer.as_default():
  tf.summary.trace_on()
  foo(1)
  foo(2)
  tf.summary.trace_export("foo")

Depending on the argument, tf.function (really, auto-graph) creates ops that are unique within GraphDef but is not globally unique. In the example above, two GraphDefs (on from foo(1) and another from foo(2)) will be written out and they can collide badly in names and content.

In such case, instead of showing wrong graph content, TensorBoard throws an error.

Start with the TensorFlow v2 tf.function and tf.summary.trace_on/trace_export flow shown in the example. Reproduce the GraphDef collision with foo(1) and foo(2), then trace where TensorBoard reconciles the resulting graphs. Done means the example no longer raises a reconciliation error or displays incorrect graph content.