code: def test_boat_marker_with_no_wind_speed_or_heading():
      m = folium.Map([30.0, 0.0], zoom_start=3)
      bm1 = plugins.BoatMarker((34, -43), heading=45, color="#8f8")
      m.add_child(bm1)
  
      out = normalize(m._parent.render())
  
      # We verify that the script part is correct.
      tmpl = Template(
          """
          var {{ this.get_name() }} = L.boatMarker(
              {{ this.location|tojson }},
              {{ this.options|tojson }}
          ).addTo({{ this._parent.get_name() }});
          {{ this.get_name() }}.setHeading({{ this.heading }});
      """
      )
  
      assert normalize(tmpl.render(this=bm1)) in out
  
imports: from jinja2 import Template
  import folium
  from folium import plugins
  from folium.utilities import normalize
label_desc: Use image node_id 2 for calling a global function with example usage: test_boat_marker_with_no_wind_speed_or_heading() without return types