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<graph> {

 "version": 2,
 "width": 300,
 "height": 50,
 "data": [
   {
     // Data is retrieved from the Wikidat Query API (SPARQL).
     "name": "table",
     "url": "wikidatasparql:///?query=SELECT+%3Finstance+%3FinstanceLabel+%3Fcount+%7B+%7B%0A++++SELECT+%3Finstance+%28COUNT%28DISTINCT+%3Fitem%29+as+%3Fcount%29+%7B%0A++++++++++%7B%3Fitem+wdt%3AP131+wd%3AQ25+.+%7D%0A++UNION+%7B+%3Fitem+wdt%3AP131+%3Fpob+.+%3Fpob+wdt%3AP131%2A+wd%3AQ25+%7D%0A++++++++++%3Fitem++wdt%3AP31+%3Finstance.%7D%0A++++GROUP+BY+%3Finstance%0A++++HAVING+%28%3Fcount+%3E+100%29%7D%0A+SERVICE+wikibase%3Alabel+%7B+bd%3AserviceParam+wikibase%3Alanguage+%22en%22.+%7D+%7D%0AORDER+BY+DESC%28%3Fcount%29%0ALIMIT+15%0AOFFSET+0",
     "format": { "type": "json" },
     "transform": [
       // sort in descending order using value as the sort key
       {"type": "sort","by": "-count"},
       // To visualize, use "pie" transformation to add layout_start, layout_end, and layout_mid fields to each {label, value} object
       // These fields contain angles at which to start and stop drawing arcs. First element's start will be 0, and last element's end will be 360 degrees (in radians)
       {"type": "pie","field": "count"}
     ]
   }
 ],
 // Scales are like functions -- marks use them to convert a data value into a visual value, like x or y coordinate on the graph, or a color value.
 "scales": [
   {
     // This scale will be used to assign a color to each slice, using a palette of 10 colors
     "name": "color",
     "domain": {"data": "table","field": "instanceLabel"},
     "range": "category10",
     "type": "ordinal"
   }
 ],
 "marks": [
   {
     // This mark draws the actual pie chart from the data source
     // Each element is an arc between layout_start and layout_end angles (as calculated by the pie transformation)
     // drawn with a given radius, stroke, and fill.
     "from": {"data": "table"},
     "type": "arc",
     "properties": {
       "enter": {
         "fill": {"scale": "color","field": "instanceLabel"},
         // Use "width" signal divided by 2 for the outer radius
         "outerRadius": {"signal": "width", "mult": 0.5},
         "startAngle": {"field": "layout_start"},
         "endAngle": {"field": "layout_end"},
         "stroke": {"value": "white"},
         "strokeWidth": {"value": 1}
       }
     }
   },
   {
     // This mark draws labels around the pie chart after the pie chart has been drawn
     "type": "text",
     // Before drawing, we need to perform a number of calculations to figure out the exact location and orientation of the text
     "from": {
       "data": "table",
       "transform": [
         // For each data point (datum), each of these transformations will be ran in order.
         // Formula transformation evaluates the expression and assigns result to the datapoint
         // Size of the pie slice, in degrees:  sliceSize = (end - start) * 180 / Pi
         { "type": "formula", "field": "sliceSize", "expr": "(datum.layout_end - datum.layout_start)*180/PI" },
         // Draw text only if the slice of the arc is more than 2 degrees to avoid overcrowding
         { "type": "filter", "test": "datum.sliceSize > 2" },
         // Determine the side of the pie chart we are on - left or right.
         { "type": "formula", "field": "invert", "expr": "datum.layout_mid*180/PI < 180 ? 1 : -1" },
         // If on the left, the text should be right-aligned (go from the rim inward)
         { "type": "formula", "field": "align", "expr": "datum.invert > 0 ? 'left' : 'right'" },
         // At what angle should the text be drawn relative to the point on the circle
         { "type": "formula", "field": "angle", "expr": "(datum.layout_mid*180/PI)-90*datum.invert" },
         // Make font smaller for smaller pie slices
         { "type": "formula", "field": "fontSize", "expr": "datum.sliceSize > 20 ? 13 : (datum.sliceSize > 10 ? 11 : 10)" },
         // Make font bold for largest pie slices 
         { "type": "formula", "field": "fontWeight", "expr": "datum.sliceSize > 15 ? 'bold' : 'normal'" }
       ]
     },
     "properties": {
       "enter": {
         // Use the fields calculated in the transformation to draw category names
         "align": {"field": "align"},
         "angle": {"field": "angle"},
         "baseline": {"value": "middle"},
         "fill": {"value": "black"},
         "fontSize": {"field": "fontSize"},
         "fontWeight": {"field": "fontWeight"},
         "radius": {"signal": "width", "mult": 0.5, "offset": 10},
         "text": {"template": "\u007b{datum.count|number:',d' }\u007d"},
         "theta": {"field": "layout_mid"}
       }
     }
   }
 ],
 // Show legend, using the scale named "color" as the source.
 "legends": [{
   "title": "Type of place",
   "fill": "color",
    "properties": {
      "title": { "fontSize": {"value": 14} },
      "symbols": { "stroke": {"value": "transparent"} },
      "legend": {
        "strokeWidth": {"value": 1.5},
        // Set new position of the legend relative to the center of the graph, using graph's width & height
        "x": {"signal":"width", "mult":0.5, "offset":60},
        "y": {"signal":"height", "mult":-0.5}
      }
    }
 }]

} </graph>See it in Wikidata Query Service