How can I post an image to Facebook using Python?
You can use the facebook provided Python SDK to upload photos using an oauth key.
Once you get the oauth key, you can upload a picture with GraphAPI.put_object():
graph = facebook.GraphAPI(oauth_access_token)
photo = open("picture.jpg", "rb")
graph.put_object("me", "photos", message="You can put a caption here", source=photo.read())