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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 step_impl04(context):
 """Compare behavior of singleton vs. non-singleton. :param context: test context. """

    single = context.singleStore
    general = context.generalStore
    key = 13
    item = 42
    assert single.request(key) == general.request(key)
    single.add_item(key, item)
    general.add_item(key, item)
    assert single.request(key) == general.request(key)