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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 kb_mapping_exists(kb_name, key):
 """Return the information if a mapping exists. :param kb_name: knowledge base name :param key: left side (mapFrom) """

    try:
        kb = get_kb_by_name(kb_name)
    except NoResultFound:
        return False
    return key in kb.kbrvals