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


    assert event.type in DATASOURCE_TYPE

    # Done packets have no dt.
    if not event.type == DATASOURCE_TYPE.DONE:
        assert isinstance(event.dt, datetime)
        assert event.dt.tzinfo == pytz.utc