Exercise$13$: Combine all United States entries together into USA. These would include the following:

'USA $\text{'},$ 'USA', $\text{'}$us$\text{'},$ 'usa', $\text{'}$Us$\text{'},\text{'}$US$\text{'},$ 'Murica', 'United States', 'united states', 'Usa', 'United States $\text{'},$ 'United staes', 'United States of America', 'United states', $\text{'}$u$.$s$.$a$.\text{'},$ 'United States of America $\text{'},$ 'america', $\text{'}$U$.$S$.$A$.\text{'},$ 'unhinged states', 'united states of america', $\text{'}$US of A$\text{'},$ 'The United States', 'North Carolina $\text{'},$ 'Unied States', $\text{'}$U S$\text{'},\text{'}$u$.$s$.\text{'},$ 'The United States of America', 'unite states',$\text{'}$U$.$S$.\text{'},$ 'USA? Hard to tell anymore..$\text{'},"\text{'}$merica$",$ 'United State', 'United Sates', 'California', 'Unites States', 'USa', 'I pretend to be from Canada, but I am really from the United States.$\text{'},$ 'Usa $\text{'},$ 'United Stated', 'New Jersey', 'United ststes', 'America', 'United Statss', 'murrika', 'USA! USA! USA!$\text{'},$ 'USAA', 'united States $\text{'},\text{'}$N$.$ America', 'USSA', $\text{'}$U$.$S$.\text{'},\text{'}$u s a$\text{'},$ 'United Statea', 'united ststes', 'USA USA USA!!!!$\text{'}$