Analyse following RPM build log snippet. Describe contents accurately, without speculation or suggestions for resolution.            
Your analysis must be as concise as possible, while keeping relevant information intact.
Snippet: 
error: Installed (but unpackaged) file(s) found:
   /usr/lib64/python3.13/lib-dynload/_testexternalinspection.cpython-313-x86_64-linux-gnu.so
   /usr/lib64/python3.13/lib-dynload/_testexternalinspection.cpython-313d-x86_64-linux-gnu.so
   /usr/lib64/python3.13/lib-dynload/_testexternalinspection.cpython-313t-x86_64-linux-gnu.so
   /usr/lib64/python3.13/lib-dynload/_testexternalinspection.cpython-313td-x86_64-linux-gnu.so
   /usr/lib64/python3.13/lib-dynload/_testlimitedcapi.cpython-313-x86_64-linux-gnu.so
   /usr/lib64/python3.13/lib-dynload/_testlimitedcapi.cpython-313d-x86_64-linux-gnu.so
   /usr/lib64/python3.13/lib-dynload/_testlimitedcapi.cpython-313t-x86_64-linux-gnu.so
   /usr/lib64/python3.13/lib-dynload/_testlimitedcapi.cpython-313td-x86_64-linux-gnu.so
There are installed but unpackaged files. This makes the build fail.