Post #378: 
Leafar:
One question, I am trying to do a symmetrical menu with all options (-X2X, X2-X, -Y2Y…) in edit mode and I want to do it without having to select all the mesh with “A” but the script I find in operator is for toggle selection and I need just select all, not deselect all, is that posible??
You can change action parameter in that operator. Use this command to select all data:
bpy.ops.mesh.select_all(action='SELECT')
Leafar:
I also want to have all the mesh selected after the operation for make another symmetry if I want to.
Just add the command before and after your command:
bpy.ops.mesh.select_all(action='SELECT'); you command here; bpy.ops.mesh.select_all(action='SELECT')