**List of steps to reproduce** (step by step, including full links if applicable):
pwb dataextend -simulate Q42
**What happens?**:
```
Found here:
VIAF ID: 171149066383365600907
date of birth: 1952
date of death: 2001
ISNI: 0000 0000 8045 6315
Save this? (Y/n) y
Adding VIAF ID: 171149066383365600907
SIMULATION: wbsetclaim action blocked.
Sourcing VIAF ID: 171149066383365600907
SIMULATION: wbsetreference action blocked.
0 pages read
0 pages written
0 pages skipped
Execution time: 50 seconds
Script terminated by exception:
ERROR: KeyError: 'reference'
Traceback (most recent call last):
File "C:\pwb\GIT\core\pwb.py", line 499, in <module>
main()
File "C:\pwb\GIT\core\pwb.py", line 483, in main
if not execute():
File "C:\pwb\GIT\core\pwb.py", line 466, in execute
run_python_file(filename, script_args, module)
File "C:\pwb\GIT\core\pwb.py", line 143, in run_python_file
exec(compile(source, filename, 'exec', dont_inherit=True),
File ".\scripts\dataextend.py", line 15458, in <module>
main()
File ".\scripts\dataextend.py", line 15454, in main
bot.run()
File "C:\pwb\GIT\core\pywikibot\bot.py", line 1571, in run
self.treat(page)
File ".\scripts\dataextend.py", line 999, in treat
createdclaim.addSources(
File "C:\pwb\GIT\core\pywikibot\page\_wikibase.py", line 1706, in addSources
claim.hash = data['reference']['hash']
KeyError: 'reference'
CRITICAL: Exiting due to uncaught exception <class 'KeyError'>
C:\pwb\GIT\core>
```
The following sourcedata is tried to be used with asddSources:
```
[Claim.fromJSON(DataSite("wikidata", "wikidata"), {'mainsnak': {'snaktype': 'value', 'property': 'P854', 'datatype': 'url', 'datavalue': {'value': 'https://authority.bibsys.no/authority/rest/authorities/html/90196888', 'type': 'string'}}, 'type': 'statement', 'rank': 'normal'}),
Claim.fromJSON(DataSite("wikidata", "wikidata"), {'mainsnak': {'snaktype': 'value', 'property': 'P1015', 'datatype': 'external-id', 'datavalue': {'value': '90196888', 'type': 'string'}}, 'type': 'statement', 'rank': 'normal'}),
Claim.fromJSON(DataSite("wikidata", "wikidata"), {'mainsnak': {'snaktype': 'value', 'property': 'P813', 'datatype': 'time', 'datavalue': {'value': {'time': '+00000002022-04-12T00:00:00Z', 'precision': 11, 'after': 0, 'before': 0, 'timezone': 0, 'calendarmodel': 'http://www.wikidata.org/entity/Q1985727'}, 'type': 'time'}}, 'type': 'statement', 'rank': 'normal'})]
```
**Software version**:
Pywikibot 7.2 with [[ https://gerrit.wikimedia.org/r/c/pywikibot/core/+/779447 | this ]] patch