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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 relation_clear(r_id=None):
    ''' Clears any relation data already set on relation r_id '''
    settings = relation_get(rid=r_id,
                            unit=local_unit())
    for setting in settings:
        if setting not in ['public-address', 'private-address']:
            settings[setting] = None
    relation_set(relation_id=r_id,
                 **settings)