cloudpickle makes it possible to serialize Python constructs not
supported by the default pickle module from the Python standard library.

cloudpickle is especially useful for cluster computing where Python
expressions are shipped over the network to execute on remote hosts,
possibly close to the data.

Among other things, cloudpickle supports pickling for lambda
expressions, functions and classes defined interactively in the
`__main__` module.

WWW: https://github.com/cloudpipe/cloudpickle