vimrc for Django development

gistfile1.vim

let g:last_relative_dir = ''
nnoremap \m :call RelatedFile ("models.py")<cr>
nnoremap \v :call RelatedFile ("views.py")<cr>
nnoremap \u :call RelatedFile ("urls.py")<cr>
nnoremap \a :call RelatedFile ("admin.py")<cr>
nnoremap \t :call RelatedFile ("templates/")<cr>
nnoremap \T :e templates/<cr>
nnoremap \S :e settings.py<cr>
nnoremap \U :e urls.py<cr>

fun! RelatedFile(file)
    if filereadable(expand("%:h"). '/models.py') || isdirectory(expand("%:h") . "/templatetags/")
        exec "edit %:h/" . a:file
        let g:last_relative_dir = expand("%:h") . '/' 
        return ''
    endif
    if g:last_relative_dir != ''
        exec "edit " . g:last_relative_dir . a:file
        return ''
    endif
    echo "Can't determine where relative file is : " . a:file
    return ''
endfun

fun SetAppDir()
    if filereadable(expand("%:h"). '/models.py') || isdirectory(expand("%:h") . "/templatetags/")
        let g:last_relative_dir = expand("%:h") . '/' 
        return ''
    endif
endfun
autocmd BufEnter *.py call SetAppDir()