Shell Game
In the Shell game involving a coin and three opaque shells positioned in a line (A, B, and C), the "banker" player makes a series of moves to change the position of two shells, keeping the coin under the shell. Given the initial position of the coin and a sequence of moves made by the "banker", you must determine the final position of the coin. The moves are: 1 - swap A and B, 2 - swap B and C, and 3 - swap A and C.
Input: Two arguments: a character (str) indicating the starting position of the coin ('A', 'B', or 'C'), and list of moves as integers (int).
Output: A character of final position.
Examples:
assert shell_game("A", [1, 2, 3]) == "A"
assert shell_game("C", [1, 2, 3, 3, 1, 1]) == "B"
assert shell_game("B", [3]) == "B"
assert shell_game("B", []) == "B"
