Where is the Symbol editor "canvas" ?

Hi friends,

 I have been using the part developer tool (v16.6) for creating the symbols but i am not able the see the symbols i have created. I understand that the symbols can be viewed in canvas. Could you please let me know how do i open/see/use this symbol editor canvas.

 Thanksin advance.

Warm regards,

Prajwal Kini A

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