Output last 3 months in one file

[Mike-Honey]

I'm trying to strike a balance between an interesting visualisation and the limits of how many shapes can be displayed in a Mapbox visual. I think a single month is too short (could be just a few days of data at the start of a month). The full historical set is too many shapes for Mapbox.

I think the right balance is around the last 3 months, e.g. currently from July to September 2019. Thats the range I've extracted manually in my current report:

https://app.powerbi.com/view?r=eyJrIjoiNzAwMjFmYjQtZDUwYi00NGZmLWFiOWMtYTI1NDBiOWQ3MTA4IiwidCI6ImRjMWYwNGY1LWMxZTUtNDQyOS1hODEyLTU3OTNiZTQ1YmY5ZCIsImMiOjEwfQ%3D%3D

Can the python script be enhanced to produce a single .geojson file with the last 3 months? This would be an alternative to the current monthly logic. Ideally the dates selected would automatically roll forward over time, or I could edit the script once a month if that is easier.

[Mike-Honey]

I'm currently achieving this with a couple of awful script hacks:

1. instead of the section: # We gather all the unique months..,
   i'm just using:
   months = ['Last-3m']

2. instead of the line starting: monthsdict[m].append(...
   i'm using:
   if m >= '201907':
   monthsdict[months[0]].append(dict(type="Feature",
   geometry=geom, properties=atr))

Obviously not ideal as I'll have to edit the script every month.