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A vector, made of 3 float coordinates. Used to represent positions or directions in 3D space.
Valid syntax: '0 0 0' or '20.5 -10 0.00001'
Note the simple quotes around the vector. Do not use double quotes, they are reserved for strings.
If you declare a vector foobar, then you can access it's x, y and z fields with: foobar_x, foobar_y,foobar_z.