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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 do_set_workdir(self, args):
 """Set the working directory. The working directory is used to load and save known devices to improve startup times. During startup the application loads and saves a file `insteon_plm_device_info.dat`. This file is saved in the working directory. The working directory has no default value. If the working directory is not set, the `insteon_plm_device_info.dat` file is not loaded or saved. Usage: set_workdir workdir Arguments: workdir: Required - Working directory to load and save devie list """

        params = args.split()
        workdir = None

        try:
            workdir = params[0]
        except IndexError:
            _LOGGING.error('Device name required.')
            self.do_help('set_workdir')

        if workdir:
            self.tools.workdir = workdir