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matplotlib.axes.Axes.yaxis_date
Axes.yaxis_date(self, tz=None)- 
    
Sets up y-axis ticks and labels that treat the y data as dates.
Parameters: - 
           
tzstr or tzinfo instance, optional - 
           
Timezone. Defaults to
rcParams["timezone"](default: 'UTC'). 
 - 
           
 
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 https://matplotlib.org/3.2.2/api/_as_gen/matplotlib.axes.Axes.yaxis_date.html