Your goal is to find the secret four-color code. The following colors are possible: black, red, white, brown, blue, green.
Some guesses have already been made. I will provide feedback for each guess made with which it is possible to unambigiously determine the secret code.

Previous Guesses:
Guess: ['black', 'red', 'green', 'brown']. Hint: one color is in the correct position and two colors are in the secret code but in the wrong position.
Guess: ['black', 'black', 'white', 'green']. Hint: one color is in the correct position.
Guess: ['blue', 'black', 'brown', 'brown']. Hint: one color is in the correct position and two colors are in the secret code but in the wrong position.
Guess: ['black', 'brown', 'brown', 'red']. Hint: three colors are in the correct positions.
A B C D
black, blue, brown, red brown, blue, green, black green, blue, brown, white brown, black, black, brown