Best portrait lens for the panasonic lumix gx8?

Here is what the site says about that.

From Panasonic Lumix GX8: Panasonic Lumix GX8: A mirrorless camera by Panasonic with a 20.3-megapixel Micro Four Thirds sensor, announced in 2015. Specs - Maker: Panasonic - Mount: Micro Four Thirds - Sensor: Micro Four Thirds, 17.3 x 13mm, crop factor 2.0 - Resolution: 20.3 megapixels - Stabilisation: in the body - Announced: 2015 - Type: mirrorless camera Focal lengths on it Lenses frame like 2.0 times their focal length on full frame: 12mm like 24mm, 18mm ...

From Portraits: Portraits: For portraits, the lens matters far more than the camera. A cheap body with a good portrait lens beats an expensive body with a kit zoom every time.

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