[Py] Canvas example (correction)

Here are some GUI examples of Python with Tkinter. One of the example shows how to draw lines in the canvas. However, the source code has some errors. I have tested and corrected the errors as the following lines:

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< x =" 250">                         y = 250 - (i * 40)
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<>                         scaled.append((100 + 3*x, 250 - (4*y)/5))
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< width="1,">                         canvas.create_oval(xs-6,ys-6,xs+6,ys+6, width=1,