message: [XLA:Python] Improve error message when converting a Python value to an buffer fails.
diff: @@ -107,7 +107,9 @@ StatusOr<std::unique_ptr<PjRtBuffer>> PyClient::PjRtBufferFromPyval(
  absl::optional<CastToArrayResult> c = CastToArray(argument);
  if (!c) {
  - return InvalidArgument("from_python argument must be an array.");
  + return InvalidArgument(
  + "from_python argument must be an array, got value %s",
  + py::cast<std::string>(py::repr(argument)));
  }
  std::shared_ptr<PythonRefManager::ManagedPyObjects> py_buffer_ref =
  