Guppi has needs the python-version it was compiled with:

| $ strings /usr/lib/libguppiuseful.so | egrep 'python|1.5.2'
| ...
| lib/python%s
| 1.5.2

When using another python version, Guppi will fail to start:

| Could not find platform independent libraries <prefix>
| Consider setting $PYTHONHOME to <prefix>[:<exec_prefix>]
| 'import exceptions' failed; use -v for traceback
| Warning!  Falling back to string-based exceptions
| 'import site' failed; use -v for traceback
| Fatal Python error: couldn't import os

Therefore, there should be an explicit 'Requires: python = <version>' where
<version> is the used python-version. Without this it is very difficulty to
determine why programs using guppi are failing (e.g. gnucash).