Python Dirble API wrapper

dirble.py

import requests
from collections import namedtuple

class Dirble(object):
    Category = namedtuple("Category", "id name description")
    Station = namedtuple("Station", "id name streamurl country bitrate status")
    StationDetails = namedtuple("StationDetails", "id name streamurl country bitrate status description added urlid website songhistory")
    Song = namedtuple("Song", "artist title")

    def __init__(self, key, base_url):
        self.key = key
        self.base_url = base_url

    def api_call(self, name, *args):
        url = "{}/{}/apikey/{}/{}".format(self.base_url, name, self.key,
                                          "/".join([str(s) for s in args]))
        r = requests.get(url)
        json = r.json()
        if type(json) == dict and "errormsg" in json:
            raise RuntimeError(json["errormsg"])
        elif type(json) == list and len(json) > 0 and "errormsg" in json[0]:
            raise RuntimeError(json[0]["errormsg"])
        return json

    def getCategories(self):
        return [Dirble.Category(d["id"], d["name"], d["description"])
                for d in self.api_call("categories")]

    def getPrimaryCategories(self):
        return [Dirble.Category(d["id"], d["name"], d["description"])
                for d in self.api_call("primaryCategories")]

    def getChildCategories(self, category_id):
        return [Dirble.Category(d["id"], d["name"], d["description"])
                for d in self.api_call("childCategories", "primaryid", category_id)]

    def getStations(self, category_id):
        return [Dirble.Station(d["id"], d["name"], d["streamurl"], d["country"], d["bitrate"], d["status"])
                for d in self.api_call("stations", "id", category_id)]

    def search(self, text, genre = None, frompage = None, count = None):
        args = []
        if genre is not None:
            args += ["genre", genre]
        if frompage is not None:
            args += ["from", frompage]
        if count is not None:
            args += ["count", count]

        return [Dirble.Station(d["id"], d["name"], d["streamurl"], d["country"], d["bitrate"], d["status"])
                for d in self.api_call("search", "search", text, *args)]

    def getContinent(self, url_id):
        return [Dirble.Station(d["id"], d["name"], d["streamurl"], d["country"], d["bitrate"], d["status"])
                for d in self.api_call("continent", "continent", url_id)]

    def getCountry(self, country_code):
        return [Dirble.Station(d["id"], d["name"], d["streamurl"], d["country"], d["bitrate"], d["status"])
                for d in self.api_call("country", "country", country_code)]

    def getStationDetails(self, station_id):
        d = self.api_call("station", "id", station_id)
        return Dirble.StationDetails(d["id"], d["name"], d["streamurl"], d["country"],
                              d["bitrate"], d["status"], d["description"], d["added"],
                              d["urlid"], d["website"],
                              [Dirble.Song(s["name"], s["title"]) for s in d["songhistory"]])


API_KEY = "<YOUR API KEY HERE>"
BASE_URL = "http://api.dirble.com/v1"
d = Dirble(API_KEY, BASE_URL)
d.search("Foo")