Best portrait lens for the olympus pen e pm2?

Here is what the site says about that.

From Olympus PEN E-PM2: Olympus PEN E-PM2: A mirrorless camera by Olympus with a 16.1-megapixel Micro Four Thirds sensor, announced in 2012. The smallest PEN, with few controls and the 16MP sensor of the first E-M5. Specs - Maker: Olympus - Mount: Micro Four Thirds - Sensor: Micro Four Thirds, 17.3 x 13mm, crop factor 2.0 - Resolution: 16.1 megapixels - Stabilisation: in the body - Announced: 2012 - Type: mirrorless camera Focal lengths on it Lenses ...

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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