How to use the wagtailvideos.forms.get_video_form function in wagtailvideos

def edit(request, video_id):
    VideoForm = get_video_form(Video)
    video = get_object_or_404(Video, id=video_id)

    if request.POST:
        original_file = video.file
        form = VideoForm(request.POST, request.FILES, instance=video)
        if form.is_valid():
            if 'file' in form.changed_data:
                # if providing a new video file, delete the old one and all renditions.
                # NB Doing this via original_file.delete() clears the file field,
                # which definitely isn't what we want...
                original_file.storage.delete(original_file.name)

                # Set new video file size
                video.file_size = video.file.size

            video = form.save()

def get_video_edit_form(VideoModel):
    VideoForm = get_video_form(VideoModel)

    # Make a new form with the file and focal point fields excluded
    class VideoEditForm(VideoForm):
        class Meta(VideoForm.Meta):
            model = VideoModel
            exclude = (
                'file',
            )

    return VideoEditForm

def chooser_upload(request):
    VideoForm = get_video_form(Video)

    searchform = SearchForm()

    if request.POST:
        video = Video(uploaded_by_user=request.user)
        form = VideoForm(request.POST, request.FILES, instance=video)

        if form.is_valid():
            video.uploaded_by_user = request.user
            video.save()

            # Reindex the video to make sure all tags are indexed
            search_index.insert_or_update_object(video)

            return render_modal_workflow(
                request, None, json_data={

def add(request):
    VideoForm = get_video_form(Video)

    if request.POST:
        video = Video(uploaded_by_user=request.user)
        form = VideoForm(request.POST, request.FILES, instance=video, user=request.user)
        if form.is_valid():
            # Save
            video = form.save(commit=False)
            video.file_size = video.file.size
            video.save()

            # Success! Send back an edit form
            for backend in get_search_backends():
                backend.add(video)

            messages.success(request, _("Video '{0}' added.").format(video.title), buttons=[
                messages.button(reverse('wagtailvideos:edit', args=(video.id,)), _('Edit'))

def add(request):
    VideoForm = get_video_form(Video)

    collections = permission_policy.collections_user_has_permission_for(request.user, 'add')
    if len(collections) > 1:
        collections_to_choose = collections
    else:
        # no need to show a collections chooser
        collections_to_choose = None

    if request.method == 'POST':
        if not request.is_ajax():
            return HttpResponseBadRequest("Cannot POST to this view without AJAX")

        if not request.FILES:
            return HttpResponseBadRequest("Must upload a file")

        # Build a form for validation

def chooser(request):
    VideoForm = get_video_form(Video)
    uploadform = VideoForm()

    videos = Video.objects.order_by('-created_at')

    q = None
    if (
        'q' in request.GET or 'p' in request.GET or 'tag' in request.GET
        or 'collection_id' in request.GET
    ):
        # this request is triggered from search, pagination or 'popular tags';
        # we will just render the results.html fragment
        collection_id = request.GET.get('collection_id')
        if collection_id:
            videos = videos.filter(collection=collection_id)

        searchform = SearchForm(request.GET)