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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 up(force=True, env=None, **kwargs):
    "Starts a new experiment"
    inventory = os.path.join(os.getcwd(), "hosts")
    conf = Configuration.from_dictionnary(provider_conf)
    provider = Enos_vagrant(conf)
    roles, networks = provider.init()
    check_networks(roles, networks)
    env["roles"] = roles
    env["networks"] = networks