我在pygame中制作俄罗斯方块，但只制作了1个方块（不是4个）。下面是block类：

# Creating an environment representing the grid (virtual one)

environment = numpy.zeros((21, 16), dtype=numpy.int32)

class Block(object) :
    def __init__(self):
        self.x, self.y, self.color, self.row, self.column = 631, 3, 0, 0, 7
        self.img = next_block
        self.mv_step = 32
        pygame.time.set_timer(pygame.USEREVENT+1, 800)
        self.is_current_block = True

    def blit_and_manage(self):
        MyScreen.blit(self.img, (self.x, self.y))
        # this makes the first line doesn't count, because very block spawns outside the grid at first and then enters it
        if self.y == 35:
            self.row = 0
        # handling events
        for e in events:
            # moving a block to the left
            if (((e.type == pygame.KEYDOWN and e.key == pygame.K_q) or (e.type == pygame.KEYDOWN and e.key == pygame.K_LEFT)) and self.x != 407) and self.is_current_block and environment[self.row, self.column-1] == 0:
                self.x -= 32
                self.column -= 1
                environment[self.row, self.column+1] = 0
            # moving a block to the right
            elif (((e.type == pygame.KEYDOWN and e.key == pygame.K_d) or (e.type == pygame.KEYDOWN and e.key == pygame.K_RIGHT)) and self.x != 887) and self.is_current_block and environment[self.row, self.column+1] == 0:
                self.x += 32
                self.column += 1
                environment[self.row, self.column-1] = 0
            # moving a block down
            if ((e.type == pygame.USEREVENT+1) or ((e.type == pygame.KEYDOWN and (e.key == pygame.K_s or e.key == pygame.K_DOWN))) and self.is_current_block) and environment[self.row+1, self.column] == 0:
                self.y += self.mv_step
                if self.y > 35:
                    self.row += 1
                    environment[self.row-1, self.column] = 0
        # preventing blocks to get outside of the grid when they reach the bottom boundary
        if self.y >= 675:
            self.y = 675
            self.is_current_block = False
        # modifying the block's corresponding coordinate in the numpy array (environment) to its corresponding color number
        if self.y > 3:
            environment[self.row, self.column] = self.color
        # preventing blocks from moving down if there is another block underneath
        if self.row != 20 and environment[self.row+1, self.column] != 0:
            self.is_current_block = False

现在，一切都很好，但只有一个错误：如果我试图用块填充垂直线（通过滥发s按钮或向下箭头，顺便说一句，我使用zqsd而不是wasd），块将彼此重叠，直到只剩下两个空间，下一个将生成的块不会在某个位置向下移动，即使它下面的空间是空的，然后游戏将冻结并变得无响应，直到我用ctrl+c进行键盘中断。您可能还没有理解这个问题，因此这里有一个快速表示：

注:

请记住，我还没有做过一个游戏的条件，所以这个问题不能涉及到一个未完成的游戏功能或类似的东西。
别忘了，每个方块的颜色值都会在方块的y值达到35时放在环境数组中的相应位置，因为正如我前面所说的，在开始时有一条额外的线，既不会在游戏的网格中绘制，也不会包含在环境数组中。
问题只发生在块首次生成的列中。
以下是发生该问题时环境变量的外观：

[[0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 5 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 6 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 5 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 3 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 5 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 3 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 6 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 6 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 5 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0]
 [0 0 0 0 0 0 0 6 0 0 0 0 0 0 0 0]]