Based on the error message and research, I can help explain what's happening and how to fix it: The error occurs because Prefect is trying to cache your task's inputs, but it can't serialize (convert to a storable format) two specific objects: 1. An

EncordUserClient

instance 2. A cryptography-related private key object (

Ed25519PrivateKey

) These objects contain complex state or system resources that can't be easily converted to a simple format for storage. Here are three ways to resolve this: 1. Disable caching for the task (simplest solution):

python
from prefect import task
from prefect.tasks import NO_CACHE

@task(cache_policy=NO_CACHE)
def your_task(client, ...):
    # your task code here
    pass

2. Create a custom cache key function that excludes the problematic arguments:

python
from prefect import task

def custom_cache_key_fn(context, *args, **kwargs):
    # Exclude the client from the cache key calculation
    # Only use other arguments for caching
    cacheable_kwargs = {k: v for k, v in kwargs.items() if k != 'client'}
    return str(cacheable_kwargs)

@task(cache_key_fn=custom_cache_key_fn)
def your_task(client, ...):
    # your task code here
    pass

3. Initialize the client inside the task (if possible):

python
from prefect import task

@task
def your_task(*args, **kwargs):
    # Create the client inside the task
    client = EncordUserClient(...)
    # your task code here
    pass

The recommended approach depends on your specific needs: - If you don't need caching for this task, use option 1 (disable caching) - If you want to cache based on other parameters but not the client, use option 2 (custom cache key) - If you can initialize the client inside the task, use option 3 (internal initialization) Remember that caching is optional in Prefect, and it's perfectly fine to disable it for tasks that work with non-serializable objects. The main goal is to ensure your workflow runs reliably, even if it means sacrificing caching for certain tasks. Would you like me to provide more specific guidance based on how you're currently using the

EncordUserClient

in your task?