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<@ULVA73B9P> In Prefect 3.6.12, I have enabled plu...
# ask-marvin
n
@Marvin In Prefect 3.6.12, I have enabled plugins, and when running a flow I get this error:
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Failed to load plugin aws
Traceback (most recent call last):
  File "/Users/nicholas/earthalytics-engine/flows/api/flooding_risk/.venv/lib/python3.12/site-packages/prefect/_experimental/plugins/manager.py", line 70, in load_entry_point_plugins
    plugin = ep.load()
             ^^^^^^^^^
  File "/Users/nicholas/earthalytics-engine/flows/api/flooding_risk/.venv/lib/python3.12/site-packages/importlib_metadata/__init__.py", line 221, in load
    module = import_module(self.module)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/nicholas/.local/share/uv/python/cpython-3.12.12-macos-aarch64-none/lib/python3.12/importlib/__init__.py", line 90, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "<frozen importlib._bootstrap>", line 1387, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1360, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1310, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 488, in _call_with_frames_removed
  File "<frozen importlib._bootstrap>", line 1387, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1360, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1331, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 935, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 999, in exec_module
  File "<frozen importlib._bootstrap>", line 488, in _call_with_frames_removed
  File "/Users/nicholas/earthalytics-engine/flows/api/flooding_risk/.venv/lib/python3.12/site-packages/prefect_aws/__init__.py", line 5, in <module>
    from .s3 import S3Bucket
  File "/Users/nicholas/earthalytics-engine/flows/api/flooding_risk/.venv/lib/python3.12/site-packages/prefect_aws/s3.py", line 14, in <module>
    from prefect import task
ImportError: cannot import name 'task' from partially initialized module 'prefect' (most likely due to a circular import) (/Users/nicholas/earthalytics-engine/flows/api/flooding_risk/.venv/lib/python3.12/site-packages/prefect/__init__.py)
This is probably due to prefect-aws, what is happening? My plugin simply adds a random env variable, so it cannot be the cause.
m
✅ thought for 139.0 seconds
Yes — this is not your env-var plugin failing. It’s Prefect trying to auto-load the installed 
prefect-aws
plugin during 
import prefect
, and in 3.6.12 that can hit a circular import bug. What’s happening With experimental plugins enabled, Prefect loads all registered 
prefect.plugins
entry points as part of import-time initialization. If 
prefect-aws
is installed, it registers an 
aws
plugin entry point, so Prefect tries to load it automatically. The import chain is effectively:
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text
import prefect
-> Prefect initializes plugins
-> loads plugin entry point "aws"
-> imports prefect_aws
-> prefect_aws.s3 does: from prefect import task
-> but prefect is still only partially initialized
-> ImportError: cannot import name 'task' from partially initialized module 'prefect'
So the message:
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text
Failed to load plugin aws
is referring to the installed 
prefect-aws
package, not your custom plugin. Why this happens specifically in 3.6.12 There was a bug in Prefect 3.6.12’s import order: plugin initialization happened before Prefect’s lazy import machinery was fully set up. That means 
from prefect import task
could fail during plugin loading. This was fixed later by moving plugin initialization to occur after 
__getattr__
is defined. Relevant fix: Fix circular import when plugins import from prefect What to do Best fix: upgrade Prefect - Upgrade to at least 
3.6.16
where this import-order bug was fixed - Prefer upgrading both Prefect and 
prefect-aws
together to compatible latest versions Temporary workarounds 1. Disable experimental plugins if you don’t need them right now:
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bash
export PREFECT_EXPERIMENTS_PLUGINS_ENABLED=0
2. Deny just the AWS plugin if you want plugins enabled but don’t need 
prefect-aws
loaded as a plugin:
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bash
export PREFECT_EXPERIMENTS_PLUGINS_DENY=aws
Bottom line - Your plugin that adds an env var is probably not the cause. - The failing plugin is 
prefect-aws
, loaded automatically because plugins are enabled. - In Prefect 
3.6.12
, this is a known initialization-order issue. - Upgrading Prefect is the right fix. If you want, I can help you pin a known-good Prefect / prefect-aws version combination for your Python 3.12 environment.
n
did you figure this one out?
n
@Nate nope, sorry. I simply disabled the aws plugin
n
👍 i was gonna ask if you had named any of your files in a way that'd conflict w the modules you'd be importing
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