Simple script to combine a bunch of GeoJson files that each specify a single Polygon into a MultiPolygon GeoJson object.

combine.py

#!/usr/bin/env python

"""
Simple script to combine a bunch of GeoJson files that each specify a single Polygon into a MultiPolygon GeoJson object.
"""

import json, sys

def combine(*args):
    combined = {"type": "MultiPolygon", "coordinates": []}
    for file in args:
        polygon = json.load(open(file))
        combined["coordinates"].append(polygon["coordinates"])
    json.dump(combined, sys.stdout)

if __name__ == "__main__":
    combine(*sys.argv[1:])