Workflow node concurrent execution failed

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Dify version

0.15.3

Cloud or Self Hosted

Cloud

Steps to reproduce

dify.txt

Import the above yaml file and input "abc" for testing. Code3 does not wait for Code4 to finish executing to get the result, resulting in the failure of Code3 execution.

✔️ Expected Behavior

Wait for code4 to finish executing, and then continue executing code3 after getting the execution result.

❌ Actual Behavior

Error message

Traceback (most recent call last): File "/var/sandbox/sandbox-python/tmp/b668d330_7d69_4e84_bed0_6d734f61d3e9.py", line 48, in <module> File "<string>", line 17, in <module> File "<string>", line 6, in main TypeError: unsupported operand type(s) for +: 'NoneType' and 'str' error: exit status 255