python: Refactor build of dictionary entries for py_get_lockspaces
    
    Use Py_BuildValue("{...}",...) for creating each dictionary entry
    in lockspaces list.
    
    Using helper for different path formats:
    - Py2: will treat path as PyString using the "s" format.
    - Py3: will treat path as PyBytes using the "y" format.
    
    Current status:
    - Py2: will build and pass tests.
    - Py3: will fail to build for missing respective API calls.