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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 onEdge(self, canvas):
 """ Returns a list of the sides of the sprite which are touching the edge of the canvas. 0 = Bottom 1 = Left 2 = Top 3 = Right """

        sides = []
        if int(self.position[0]) <= 0:
            sides.append(1)

        if (int(self.position[0]) + self.image.width) >= canvas.width:
            sides.append(3)

        if int(self.position[1]) <= 0:
            sides.append(2)

        if (int(self.position[1]) + self.image.height) >= canvas.height:
            sides.append(0)

        return sides