Python: UUID storage from dictionary of Python IDs

**Description of the false positive**

I generate UUID's from python's `uuid` module just as a reference. However LGTM gives me `Sensitive data (id) is stored here.` This may be because I use a dictionary of Python object IDs to their UUID, but the IDs aren't written to the file.

**URL to the alert on the project page on LGTM.com**

https://lgtm.com/projects/g/pyunity/pyunity/snapshot/d0cab0520cfd076e153275fffe37c385d32400ea/files/pyunity/loader.py#xdf524e534b51d84c:1
https://lgtm.com/projects/g/pyunity/pyunity/snapshot/d0cab0520cfd076e153275fffe37c385d32400ea/files/pyunity/loader.py#x144beaea4b90ea38:1
https://lgtm.com/projects/g/pyunity/pyunity/snapshot/d0cab0520cfd076e153275fffe37c385d32400ea/files/pyunity/files.py#x2fcdbce9cb89ebb1:1
https://lgtm.com/projects/g/pyunity/pyunity/snapshot/d0cab0520cfd076e153275fffe37c385d32400ea/files/pyunity/loader.py#x8c3e41fa3f8844c9:1