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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 assert_trade_protocol(event):
 """Assert that an event meets the protocol for datasource TRADE outputs."""

    assert_datasource_protocol(event)

    assert event.type == DATASOURCE_TYPE.TRADE
    assert isinstance(event.price, numbers.Real)
    assert isinstance(event.volume, numbers.Integral)
    assert isinstance(event.dt, datetime)