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matplotlib.axes.Axes.relim
Axes.relim(visible_only=False)- 
    
Recompute the data limits based on current artists. If you want to exclude invisible artists from the calculation, set
visible_only=TrueAt present,
Collectioninstances are not supported. 
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 http://matplotlib.org/2.0.2/api/_as_gen/matplotlib.axes.Axes.relim.html