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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 extend_values(dictionary, key, items):
 """Extend the values for that key with the items"""

    values = dictionary.get(key, [])
    try:
        values.extend(items)
    except TypeError:
        raise TypeError('Expected a list, got: %r' % items)
    dictionary[key] = values