Setting the Drawing color

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The color() function sets the drawing color.

An argument in the range 0 to 255 sets a grayscale value
  where 0 is black and 255 is white.
Add the statements:
color(127);
point(200, 50);
and run to display a gray point (the same size as before).

The color() also accepts a tuple of 3 values.
This results in a 24-bit RGB Truecolor.