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matplotlib.artist.Artist.get_snap
Artist.get_snap()- 
    
Returns the snap setting which may be:
- True: snap vertices to the nearest pixel center
 - False: leave vertices as-is
 - None: (auto) If the path contains only rectilinear line segments, round to the nearest pixel center
 
Only supported by the Agg and MacOSX backends.
 
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 http://matplotlib.org/2.0.2/api/_as_gen/matplotlib.artist.Artist.get_snap.html