How to use the jovian.utils.credentials.read_webapp_url function in jovian

username = owner['username']

    # Cache slug for further commits
    set_notebook_slug(filename, slug)

    # Attach environment, files and outputs
    _capture_environment(environment, slug, version)
    _attach_files(files, slug, version, exclude_files=filename)
    _attach_files(outputs, slug, version, output=True)

    if not git_message or git_message == 'auto':
        git_message = message or 'jovian commit ' + username + '/' + title + ' v' + str(version)
    _perform_git_commit(filename, git_commit, git_message)
    _attach_records(slug, version)

    log('Committed successfully! ' + urljoin(read_webapp_url(), username, title))

    return urljoin(read_webapp_url(), username, title)

log('Creating a new project "' + username + '/' + project_title + '"')
        return project_title, None

    # Extract information from metadata
    username = metadata['owner']['username']
    project_title = metadata['title']
    project_id = metadata['slug']

    # Check if the current user can commit to this project
    permissions = api.get_gist_access(project_id)
    if not permissions['write']:
        return project_title, None

    # Log whether this is an update or creation
    if project_id is None:
        log('Creating a new notebook on ' + read_webapp_url())
    else:
        log('Updating notebook "' + username + "/" + project_title + '" on ' + read_webapp_url())

    return project_title, project_id

# Extract information from metadata
    username = metadata['owner']['username']
    project_title = metadata['title']
    project_id = metadata['slug']

    # Check if the current user can commit to this project
    permissions = api.get_gist_access(project_id)
    if not permissions['write']:
        return project_title, None

    # Log whether this is an update or creation
    if project_id is None:
        log('Creating a new notebook on ' + read_webapp_url())
    else:
        log('Updating notebook "' + username + "/" + project_title + '" on ' + read_webapp_url())

    return project_title, project_id