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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 _pixelsize(self, p):
 """Calculate line width necessary to cover at least one pixel on all axes."""

        xpixelsize = 1./float(p.xdensity)
        ypixelsize = 1./float(p.ydensity)
        return max([xpixelsize,ypixelsize])