Cannot execute python-3.9.1-macosx10.9.pkg on Big Sur (11.1)

I’ve seen this problem online but no solutions thus far.

I am unable to install Python using the “pkg” installer on Mac 11.1.

The error is: “The operation couldn’t be completed. ( error -1.) Couldn’t open “python-3.9.1-macos11.0.pkg”.”

I’ve tried several versions, but none work.

Any ideas for workarounds or when this will be fixed?

Thanks in advance.