sys.excepthook error generating a PyObjc exception

autodmg_output.py

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2015-12-28 09:35:29.059 AutoDMG[1429:313432] PyObjC: Converting exception to Objective-C:
sys.excepthook is missing
lost sys.stderr
2015-12-28 09:35:29.059 AutoDMG[1429:313440] PyObjC: Converting exception to Objective-C:
sys.excepthook is missing
lost sys.stderr
2015-12-28 09:35:29.059 AutoDMG[1429:313434] PyObjC: Converting exception to Objective-C:
sys.excepthook is missing
lost sys.stderr
2015-12-28 09:35:29.059 AutoDMG[1429:313440] *** Terminating app due to uncaught exception 'OC_PythonException', reason: '<type 'exceptions.AttributeError'>: 'NoneType' object has no attribute 'close''
*** First throw call stack:
(
	0   CoreFoundation                      0x00007fff8fbd003c __exceptionPreprocess + 172
	1   libobjc.A.dylib                     0x00007fff8c77276e objc_exception_throw + 43
	2   CoreFoundation                      0x00007fff8fbcfbd9 -[NSException raise] + 9
	3   _objc.so                            0x000000010e3aca8b PyObjCErr_ToObjCWithGILState + 46
	4   _objc.so                            0x000000010e39952d PyObjCFFI_MakeClosure + 5097
	5   libffi.dylib                        0x00007fff8ef26a07 ffi_closure_unix64_inner + 511
	6   libffi.dylib                        0x00007fff8ef260c6 ffi_closure_unix64 + 70
	7   libsystem_pthread.dylib             0x00007fff8f7de05a _pthread_body + 131
	8   libsystem_pthread.dylib             0x00007fff8f7ddfd7 _pthread_body + 0
	9   libsystem_pthread.dylib             0x00007fff8f7db3ed thread_start + 13
)
libc++abi.dylib: terminating with uncaught exception of type NSException
2015-12-28 09:35:29.059 AutoDMG[1429:313432] *** Terminating app due to uncaught exception 'OC_PythonException', reason: '<type 'exceptions.AttributeError'>: 'NoneType' object has no attribute 'read''
*** First throw call stack:
(
	0   CoreFoundation                      0x00007fff8fbd003c __exceptionPreprocess + 172
	1   libobjc.A.dylib                     0x00007fff8c77276e objc_exception_throw + 43
	2   CoreFoundation                      0x00007fff8fbcfbd9 -[NSException raise] + 9
	3   _objc.so                            0x000000010e3aca8b PyObjCErr_ToObjCWithGILState + 46
	4   _objc.so                            0x000000010e39952d PyObjCFFI_MakeClosure + 5097
	5   libffi.dylib                        0x00007fff8ef26a07 ffi_closure_unix64_inner + 511
	6   libffi.dylib                        0x00007fff8ef260c6 ffi_closure_unix64 + 70
	7   libsystem_pthread.dylib             0x00007fff8f7de05a _pthread_body + 131
	8   libsystem_pthread.dylib             0x00007fff8f7ddfd7 _pthread_body + 0
	9   libsystem_pthread.dylib             0x00007fff8f7db3ed thread_start + 13
)