def toposimplify(geojson, p):
        """
        Convert geojson and simplify topology.

        geojson is a dict representing geojson.
        p is a simplification threshold value between 0 and 1.
        """
        proc_out = subprocess.run(
            ['geo2topo'],
            input=bytes(
                json.dumps(geojson),
                'utf-8'),
            stdout=subprocess.PIPE
        )
        proc_out = subprocess.run(
            ['toposimplify', '-P', p],
            input=proc_out.stdout,
            stdout=subprocess.PIPE,
            stderr=subprocess.DEVNULL
        )
        topojson = json.loads(proc_out.stdout)
        # Standardize object name
        topojson['objects']['divisions'] = topojson['objects'].pop('-')
        return topojson