python3-rosidl binary package in Ubuntu Lunar amd64

 This package is part of ROS 2, the Robot Operating System. ROS 2 uses the OMG
 Data Distribution Standard (DDS) as middleware layer, which in turn relies on
 the Interface Definition Language (IDL) to define the messages which can be
 exchanged between ROS network participants. For historical reasons, ROS has
 its own message definition format; the ROS 2 IDL support layer is responsible
 for transforming the ROS message format to the IDL format.
 .
 This package provides the Python API to parse .msg/.srv/.action files and
 convert them to .idl, parse .idl files for dynamic type support, and some
 additional helper functions.

Source package