Flask-SQLAlchemy pagination error: Could not build url for endpoint with values [‘page’]

Solution
@main.route('/collections/', defaults={"page": 1})
    def all_collections(page):
        ...
@main.route('/collections/')
@main.route('/collections/', defaults={'page': 1}  # if no page is asked for-- return page 1.
    def all_collections(page):
        ...