I have a python caller that is failing and giving me a key error

here is the log message:

2020-09-01 10:34:39| 636.8| 0.0|INFORM|Found 561025 features

2020-09-01 10:34:39| 636.8| 0.0|INFORM|Consisting of 26411 transformers, 160252 nodes and 374362 bits of conductor

2020-09-01 10:34:47| 637.9| 1.1|WARN |Python Exception <KeyError>: u'5405483'

2020-09-01 10:34:47| 637.9| 0.0|WARN |Traceback (most recent call last):

File "<string>", line 119, in close

KeyError: u'5405483'

2020-09-01 10:34:47| 637.9| 0.0|FATAL |PythonCaller_2 (PythonFactory): PythonFactory failed to close properly

2020-09-01 10:34:53| 643.8| 5.9|ERROR |PythonCaller_2 (PythonFactory): A fatal error has occurred. Check the logfile above for details

The python script is attached

The thing is, it ran perfectly OK one day and then the next day when i ran it and ever since it has kept failing. No changes to the workbench,but data updates overnight. The value referenced ' 5405483', is in both source tables that are read into the python caller, so should be found, but is not. This value changes each day. But I have checked back with previous version of the results and source table and this feature has not changed.

Just at a complete loss, it's also not my code and I am very rusty with python.

I ma probably missing something really simple, but just can not see it.

let me know if there is anything needed t unpick this problem.

Thanks everyone.

Cheers

Jacky

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