schema_serializer_workaround.py

from pydantic import BaseModel
from pydantic_core._pydantic_core import SchemaSerializer

# This also works with vanilla pickle
import cloudpickle

# Storing these as globals as a workaround.
# We should store them as instance attributes.
schema_cache, config_cache = None, None

def new_init(self, schema, config):
    global schema_cache, config_cache
    schema_cache = schema
    config_cache = config

SchemaSerializer.__init__ = new_init

def new_reduce(self):
  global schema_cache, config_cache
  return SchemaSerializer, (schema_cache, config_cache, )

SchemaSerializer.__reduce__ = new_reduce

class SimpleModel(BaseModel):
      val: int
  
sm = SimpleModel(val=5)

NewSimpleModel = cloudpickle.loads(cloudpickle.dumps(SimpleModel))
new_sm = NewSimpleModel(val=5)
print(sm == new_sm)