```bash
$ flake8 python/scripts --select F
python/scripts/generateshader.py:28:13: F841 local variable 'result' is assigned to but never used
python/scripts/generateshader.py:86:16: F821 undefined name 'err'
python/scripts/generateshader.py:87:43: F821 undefined name 'err'
python/scripts/genmdl.py:8:1: F401 'string' imported but unused
python/scripts/genmdl.py:344:5: F841 local variable 'LIBRARY' is assigned to but never used
python/scripts/genmdl.py:525:21: F841 local variable 'outputvalue' is assigned to but never used
python/scripts/mxdoc.py:6:1: F401 'os' imported but unused
python/scripts/mxformat.py:7:1: F401 'sys' imported but unused
python/scripts/mxvalidate.py:6:1: F401 'os' imported but unused
python/scripts/mxvalidate.py:28:16: F821 undefined name 'err'
python/scripts/mxvalidate.py:29:19: F821 undefined name 'err'
```

With this patch:
```bash
$ flake8 python/scripts --select F --count
0
```

Found while working on AcademySoftwareFoundation#1595.

This commit follows 83ae82e.

Signed-off-by: Stefan Habel <[email protected]>

…fixes