import anywidget
import traitlets

class CounterWidget(anywidget.AnyWidget):
    # Widget front-end JavaScript code
    _esm = """
    function render({ model, el }) {
      let button = document.createElement("button");
      button.innerHTML = `count is ${model.get("value")}`;
      button.addEventListener("click", () => {
        model.set("value", model.get("value") + 1);
        model.save_changes();
      });
      model.on("change:value", () => {
        button.innerHTML = `count is ${model.get("value")}`;
      });
      el.appendChild(button);
    }
    export default { render };
    """
    # Stateful property that can be accessed by JavaScript & Python
    value = traitlets.Int(0).tag(sync=True)

import pathlib
import anywidget
import traitlets

class CounterWidget(anywidget.AnyWidget):
    _esm = pathlib.Path("index.js")
    _css = pathlib.Path("styles.css")
    value = traitlets.Int(0).tag(sync=True)