import datetime
import urllib
import json

class WmataError(Exception):
    pass

class Wmata(object):

    base_url = 'http://api.wmata.com/%(svc)s.svc/json/%(endpoint)s'
    # By default, we'll use the WMATA demonstration key
    api_key = 'kfgpmgvfgacx98de9q3xazww' 

    def __init__(self, api_key=None):
        if api_key is not None:
            self.api_key = api_key

Add WmataError class and start of Wmata class.
Add WmataError class and start of Wmata class.

Starts module code.  Error class is added, and the main class, Wmata, is added,
with the default class variables and the init function added.
