Find centroid for Polygon

get-centroid.py

from itertools import ifilter
from shapely.geometry import Polygon
from simplegeo import context

client = context.Client('your-key','your-secret')
context_response = client.get_context(37.775255,-122.40289)
neighborhood = next(ifilter(lambda feature: feature['classifiers'][0]['category'] == 'Neighborhood', context_response['features']), None)
neighborhood_handle = neighborhood['handle']
neighborhood_boundary = Polygon(client.get_feature(neighborhood_handle).to_dict()['geometry']['coordinates'][0])
centroid = neighborhood_boundary.centroid.wkt
print centroid