plt. What does it mean when linestyle, marker, color equals none in plot()

None Is a special object , Usually used as a placeholder , Replace by default .

So in plt.plot() in ：

• linestyle = None Indicates the default solid line style
• linesyle = " " It means there is no line
• linestyle = "--" Said the dotted line
• marker=None Indicates the default tag , The default tag happens to have no tag at all  
• color=None Representing color matplotlib Default blue