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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 _get_slope(self):
 """Return a float of the increase in y divided by the increase in x, both from left to right."""

        orig = self.origin
        dest = self.destination
        ox = orig.x
        oy = orig.y
        dx = dest.x
        dy = dest.y
        if oy == dy:
            return 0
        elif ox == dx:
            return None
        else:
            rise = dy - oy
            run = dx - ox
            return rise / run