Best portrait lens for the leica m10 monochrom?

Here is what the site says about that.

From Leica M10 Monochrom: Leica M10 Monochrom: A rangefinder by Leica with a 40.9-megapixel full frame sensor, announced in 2020. Black and white only, on a 40-megapixel sensor. Specs - Maker: Leica - Mount: Leica M - Sensor: Full frame, 36 x 24mm, crop factor 1.0 - Resolution: 40.9 megapixels - Stabilisation: none in the body; use stabilised lenses for slow shutter speeds - Announced: 2020 - Type: rangefinder Focal lengths on it Full frame is the ...

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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