Deletes the part category identified by `partCategoryId`. 
This removes the category from the classification hierarchy; parts still assigned to this category or child categories that reference it as a 
parent may be affected depending on database constraints, so confirm the category is unused before deleting.

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### Parameters
**partCategoryId** `Integer`: Id of part category to delete<br />
**userId** `Integer`:Id of the user executing the function<br />

---
### Returns
**# of records modified** `Integer`<br />
**message** `String` None if success<br />

---
### Example
```python
# Delete an unused "Fasteners" part category
partCategoryId = 27
userId = system.kanoa.security.getIDPUserId({'userName': 'SYSTEM'})
recordsModified, message = system.kanoa.inventory.deletePartCategory(partCategoryId, userId)
print recordsModified, message
```