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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 auth_with_token(token, tenant_id=None, tenant_name=None, region=None):
 """ If you already have a valid token and either a tenant ID or name, you can call this to configure the identity and available services. """

    global regions, services
    identity.auth_with_token(token, tenant_id=tenant_id,
            tenant_name=tenant_name)
    regions = tuple(identity.regions)
    services = tuple(identity.services.keys())
    connect_to_services(region=region)