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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 execute_managed_notebook( cls, nb_man, kernel_name, log_output=False, start_timeout=60, execution_timeout=None, **kwargs ):
 """ Performs the actual execution of the parameterized notebook locally. Args: nb (NotebookNode):
 Executable notebook object. kernel_name (str):
 Name of kernel to execute the notebook against. log_output (bool):
 Flag for whether or not to write notebook output to stderr. start_timeout (int):
 Duration to wait for kernel start-up. execution_timeout (int):
 Duration to wait before failing execution (default: never). Note: The preprocessor concept in this method is similar to what is used by `nbconvert`, and it is somewhat misleading here. The preprocesser represents a notebook processor, not a preparation object. """

        preprocessor = PapermillExecutePreprocessor(
            timeout=execution_timeout,
            startup_timeout=start_timeout,
            kernel_name=kernel_name,
            log=logger,
        )
        preprocessor.log_output = log_output
        preprocessor.preprocess(nb_man, kwargs)