Your goal is to find the secret four-color code. The following colors are possible: black, white, green, purple, brown, yellow.
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: ['white', 'black', 'purple', 'brown']. Hint: one color is in the correct position and one color is in the secret code but in the wrong position.
Guess: ['black', 'black', 'green', 'brown']. Hint: two colors are in the correct positions.
Guess: ['green', 'purple', 'yellow', 'brown']. Hint: one color is in the correct position and three colors are in the secret code but in the wrong position.
A B C D
green, yellow, yellow, brown purple, yellow, green, brown green, brown, black, white yellow, green, green, white