TypeError: 'zip' object is not subscriptable

from future_builtins import zip

def find_spiral_2(matrix):
    "Return list of elements of matrix in clockwise spiral order."
    h, w = len(matrix), len(matrix[0]) # Height and width of remainder
    i, j = 0, -1                # Current position in spiral
    di, dj = 0, 1               # Current direction of movement
    spiral = []
    while h > 0:
        # Output top row
        for _ in range(w):
            i += di
            j += dj
            spiral.append(matrix[i][j])
        # Remove top row and rotate quarter-turn
        h, w = w, h - 1
        di, dj = dj, -di
    return spiral

def find_spiral_2(matrix):
    "Generate elements of matrix in clockwise spiral order."
    h, w = len(matrix), len(matrix[0]) # Height and width of remainder
    i, j = 0, -1                # Current position in spiral
    di, dj = 0, 1               # Current direction of movement
    while h > 0:
        # Output top row
        for _ in range(w):
            i += di
            j += dj
            yield matrix[i][j]
        # Remove top row and rotate quarter-turn
        h, w = w, h - 1
        di, dj = dj, -di