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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 find_action_name_by_value(registry, target_action_instance):
 """the association of a name of an action class with a human readable string is exposed externally only at the time of argument definitions. This routine, when given a reference to argparse's internal action registry and an action, will find that action and return the name under which it was registered. """

    target_type = type(target_action_instance)
    for key, value in six.iteritems(registry['action']):
        if value is target_type:
            if key is None:
                return 'store'
            return key
    return None