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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 require_server(fn):
 """ Checks if the user has called the task with a server name. Fabric tasks decorated with this decorator must be called like so:: fab <server name> <task name> If no server name is given, the task will not be executed. """

    @wraps(fn)
    def wrapper(*args, **kwargs):
        if env.machine is None:
            abort(red('ERROR: You must provide a server name to call this'
                      ' task!'))
        return fn(*args, **kwargs)
    return wrapper