code: def ipynb_vega_init():
      """Initialize the IPython notebook display elements
  
      This function borrows heavily from the excellent vincent package:
      http://github.com/wrobstory/vincent
      """
      try:
          from IPython.core.display import display, HTML
      except ImportError:
          print("IPython Notebook could not be loaded.")
  
      require_js = """
      if (window['d3'] === undefined) {{
          require.config({{ paths: {{d3: "http://d3js.org/d3.v3.min"}} }});
          require(["d3"], function(d3) {{
            window.d3 = d3;
            {0}
          }});
      }};
      if (window['topojson'] === undefined) {{
          require.config(
              {{ paths: {{topojson: "http://d3js.org/topojson.v1.min"}} }}
              );
          require(["topojson"], function(topojson) {{
            window.topojson = topojson;
          }});
      }};
      """
      d3_geo_projection_js_url = (
          "http://d3js.org/d3.geo.projection.v0.min.js"
      )
      d3_layout_cloud_js_url = (
          "http://wrobstory.github.io/d3-cloud/" "d3.layout.cloud.js"
      )
      topojson_js_url = "http://d3js.org/topojson.v1.min.js"
      vega_js_url = "http://trifacta.github.com/vega/vega.js"
  
      dep_libs = """$.getScript("%s", function() {
          $.getScript("%s", function() {
              $.getScript("%s", function() {
                  $.getScript("%s", function() {
                          $([IPython.events]).trigger("vega_loaded.vincent");
                  })
              })
          })
      });""" % (
          d3_geo_projection_js_url,
          d3_layout_cloud_js_url,
          topojson_js_url,
          vega_js_url,
      )
      load_js = require_js.format(dep_libs)
      html = "<script>" + load_js + "</script>"
      display(HTML(html))
  
label_desc: Use image node_id 1 for calling a global function with example usage: ipynb_vega_init() without return types