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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 add_namespace(self, name, a_namespace):
 """as we build up argparse, the actions that define a subparser are translated into configman options. Each of those options must be tagged with the value of the subparse to which they correspond."""

        # save a local copy of the namespace
        self.namespaces[name] = a_namespace
        # iterate through the namespace branding each of the options with the
        # name of the subparser to which they belong
        for k in a_namespace.keys_breadth_first():
            an_option = a_namespace[k]
            if not an_option.foreign_data:
                an_option.foreign_data = DotDict()
            an_option.foreign_data['argparse.owning_subparser_name'] = name