message: Use pybind_extension instead of py_extension.
diff: #include "absl/strings/str_cat.h"
  #include "absl/strings/str_join.h"
  #include "absl/synchronization/mutex.h"
  +// placeholder for dllexport_macros.h
  #include "tink/catalogue.h"
  #include "tink/core/key_manager_impl.h"
  #include "tink/core/key_type_manager.h"
  