Pickling bug in ApiResponse

[embray]

The ApiResponse class has an unsafe __getattr__ (

elastic-transport-python/elastic_transport/_response.py

Line 97 in 6d6e64a

def __getattr__(self, attr: str) -> Any:

) in the context of restoring from a pickled object.

When loading the object from a pickle, the unpickler tries to look up the __setstate__ attribute, but since self._body is not set yet either, this results in an infinite recursion.

Safest bet is probably just to define __getstate__ and __setstate__ on this class, e.g.

def __getstate__(self):
    return (self._body, self._meta)

def __setstate__(self, state):
    self._body, self._meta = state