The exception was the concept of a unicameral legislature.
The Declaration of Independence was adopted on the July 4, 1776 and proved that ideals can only be possible if the American resident rule themselves with its rule.
In conclusion, the exception to the significant ot the Declaration of Independence in creation of the Constitution is concept of a unicameral legislature.
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2) Cuba gained commonwealth status
3) The United States gained Cuba as a colony
4) Cuba became independent of Spain