git rm doesn't work

Couldn't remove files from repository with gittle.
# -_\- coding: utf-8 -_-

import os
import gittle

if **name** == '**main**':

```
repository = os.path.abspath(r'.\data\altium\models')
store = gittle.Gittle(repository)

print store.removed_files
store.rm(store.removed_files)
print store.removed_files
```
