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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def solid(self, x, y):
 """ Determine whether the pixel x,y is nonzero Parameters x, y : int The pixel of interest. Returns ------- solid : bool True if the pixel is not zero. """

        if not(0 <= x < self.xsize) or not(0 <= y < self.ysize):
            return False
        if self.data[x, y] == 0:
            return False
        return True