/hsize 400 def /vsize 400 def /hoff 10 def /voff 10 def
/N 1000 def
/xx [ N { rand 10000 mod 10000 div} repeat ] def
/yy [ N { rand 10000 mod 10000 div} repeat ] def
/sz [ N { rand 10000 mod 10000 div 2 mul .5 add } repeat ] def

0 1 N 1 sub { /ii exch def
        xx ii get hsize mul hoff add
        yy ii get vsize mul voff add
        sz ii get 0 360 arc fill
      } for

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