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User environment

broker version: 1b74fe0

Issue Description

when running a python function without specify the crypto_spec.cryptoKeyReaderConfig, it runs well but will reports an error log:

[2025-09-25 07:26:59 +0000] [ERROR] python_instance.py: Failed to load the crypto key reader from spec: , error: Expecting value: line 1 column 1 (char 0)

Error messages

[2025-09-25 07:26:59 +0000] [ERROR] python_instance.py: Failed to load the crypto key reader from spec: , error: Expecting value: line 1 column 1 (char 0)

Reproducing the issue

1. start the pulsar standalone
2. create a python function:

pulsar-admin functions craete --py pulsar-functions/python-examples/exclamation_function.py --name package-python-fn --classname exclamation_function.ExclamationFunction --inputs persistent://public/default/package-py-fn-input --output persistent://public/default/package-py-fn-output

3. check the function logs

Additional information

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