title: Export properties into .geojson file using geopandas
body: <p>I have a script that creates a lot of Polygons using Shapely and then exports them as .geojson files. See toy example below</p>
  <pre><code>from shapely.geometry import Polygon
  import geopandas
  
  roi = Polygon([(0,0), (0,1), (1,0), (1,1)])
  rois = [roi, roi]
  
  geopandas.GeoSeries(rois).to_file(&quot;detection_data.geojson&quot;, driver='GeoJSON')
  </code></pre>
  <p>However, I also have a list of numbers, each number is associated with one ploygon. Is there a way to export this with the GeoJSON file inside properties?</p>
  <p>For example, if I have a list:</p>
  <pre><code>detection_prob = [0.8, 0.9]
  </code></pre>
  <p>In the .geojson file I would like the properties section for the first polygon to read</p>
  <blockquote>
  <p>&quot;properties&quot;:{&quot;detection_prob&quot;:0.8}</p>
  </blockquote>
  <p>and for the second polygon</p>
  <blockquote>
  <p>&quot;properties&quot;:{&quot;detection_prob&quot;:0.9}</p>
  </blockquote>
  <p>etc etc etc... in the outputted GeoJSON file.</p>