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matplotlib.axis.XAxis.set_label_text
XAxis.set_label_text(self, label, fontdict=None, **kwargs)- 
    
Set the text value of the axis label.
Parameters: - 
           
labelstr - 
           
Text string.
 - 
           
fontdictdict - 
           
Text properties.
 - **kwargs
 - 
           
Merged into fontdict.
 
 - 
           
 
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 https://matplotlib.org/3.2.2/api/_as_gen/matplotlib.axis.XAxis.set_label_text.html