Shrimp and Okra Gumbo

1 pound okra
2 tablespoons vegetable oil
1/4 cup butter
2 large onions
2 green bell peppers
1/4 cup all-purpose flour
1 (1 pound 12 ounce) can tomatoes
2 (13 3/4 ounce) cans chicken broth
2 cups water
2 bay leaves
1/4 teaspoon leaf thyme, crunched
1/4 teaspoon hot pepper sauce
2 teaspoons salt
1 pound shrimp (or more)
Hot, cooked rice
Gumbo file, as desired

Heat oil and butter in heavy saucepan over medium heat. Saut