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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 _sanitise_list(arg_list):
 """A generator for iterating through a list of gpg options and sanitising them. :param list arg_list: A list of options and flags for GnuPG. :rtype: generator :returns: A generator whose next() method returns each of the items in ``arg_list`` after calling ``_sanitise()`` with that item as a parameter. """

    if isinstance(arg_list, list):
        for arg in arg_list:
            safe_arg = _sanitise(arg)
            if safe_arg != "":
                yield safe_arg