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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 check_arguments(cls, conf):
 """ Sanity checks for options needed for configfile mode. """

        try:
            # Check we have access to the config file
            f = open(conf['file'], "r")
            f.close()
        except IOError as e:
            raise ArgsError("Cannot open config file '%s': %s" %
                            (conf['file'], e))