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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 login_required(func):
    '''decorator describing User methods that need to be logged in'''
    def ret(obj, *args, **kw):
        if not hasattr(obj, 'sessionToken'):
            message = '%s requires a logged-in session' % func.__name__
            raise ResourceRequestLoginRequired(message)
        return func(obj, *args, **kw)
    return ret