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              ]
            }
          }
        },
        {
          id: 'medium',
          type: 'fill',
          source: 'burwell_medium',
          'source-layer': 'units',
          minzoom: 6,
          maxzoom: 10,
          paint: {
            'fill-color': {
              'property': 'color',
              'type': 'identity'
            },
          }
        },
        {
          id: 'medium_stroke',
          type: 'line',
          source: 'burwell_medium',
          '