def test_clear_matrix():
b = Board(10, 22)
for i in range(10):
for j in range(22):
b.fill_matrix(b.board_tetrominos_matrix, i, j)
b.clear_matrix(b.board_tetrominos_matrix)
for i in range(10):
for j in range(22):
assert b.board_tetrominos_matrix[i][j] == 0
