\begin{center}
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\psset{SphericalCoor=true,viewpoint=50 -20 30,Decran=50}
\begin{pspicture*}(-5,-4)(6,9)
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   intersectionplan={[1 0 .5 2] 1 [1 0 .5 -1]},
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   intersectioncolor=(bleu) (orange) (rouge),
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\end{center}