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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def cli(ctx):
 """ This is a command line app to get useful stats from a trello board and report on them in useful ways. Requires the following environment varilables: TRELLOSTATS_APP_KEY=<your key here> TRELLOSTATS_APP_TOKEN=<your token here> """

    ctx.obj = dict()
    ctx.obj['app_key'] = os.environ.get('TRELLOSTATS_APP_KEY')
    ctx.obj['app_token'] = os.environ.get('TRELLOSTATS_APP_TOKEN')
    init_db(db_proxy)