docs: def get(self, slug, xdata, ydatasets, label, opts, style, ctype):
          """
          Returns html for a chart
          """
          xdataset = self._format_list(xdata)
          width = "100%"
          height = "300px"
          if opts is not None:
              if "width" in opts:
                  width = str(opts["width"])
              if "height" in opts:
                  height = str(opts["height"])
          stylestr = '<style>#container_' + slug + \
              ' { width:' + width + ' !important; height:' + \
              height + ' !important}</style>\n'
          html = stylestr
          html += '<div id="container_' + slug + \
              '"><canvas id="canvas_' + slug + '"></canvas></div>\n'
          html += '<script>\n'
          html += 'var data = {\n'
          html += 'labels: ' + xdataset + ',\n'
          html += 'datasets:[\n'
          colors = None
          if "color" in style:
              colors = style["color"]
          i = 0
          for dataset in ydatasets:
              name = dataset["name"]
              data = dataset["data"]
              html += self._get_dataset(data, name, colors)
              if i < len(ydatasets) - 1:
                  html += ","
              i += 1
          html += ']\n'
          html += '}\n'
  
          html += 'window.onload = function() {'
          html += 'var ctx = document.getElementById("canvas_' + \
                  slug + '").getContext("2d");'
          html += 'window.myChart = new Chart(ctx, {'
          html += 'type: "' + ctype + '",'
          html += 'data: data,'
          html += 'options: {'
          html += 'spanGaps: false,'
          html += 'responsive: true,'
          html += 'maintainAspectRatio: false,'
          if "legend" in opts:
              html += 'legend: {'
              html += 'position: "' + opts["legend"] + '",'
              html += '},'
          else:
              html += 'legend: {'
              html += 'display: false,'
              html += '},'
          if "title" in opts:
              html += 'title: {'
              html += 'display: true,'
              html += 'text: "' + opts["title"] + '"'
              html += '}'
          html += '}'
          html += '});'
          html += '};'
          html += '</script>\n'
          return html