def METHOD_NAME(cls, project):
    """Method called to retrieve the url used to check for new version
    of the project provided, project that relies on the backend of this plugin.
    Attributes:
        project (:obj:`anitya.db.models.Project`): Project object whose backend
            corresponds to the current plugin.
    Returns:
        str: url used for version checking
    """
    url = f"https://crandb.r-pkg.org/{project.name}/all"
    return url