graphing with matplotlib pyplot the labels parameter is an optional parameter that can take sequence of strings that are used to provide labels for each wedge the autopct parameter takes string (or functionto be used to format the numeric values used with each wedge the counterclockwise parameter by default wedges are plotted counter clockwise in pyplot and so to ensure that the layout is more like the traditional clockwise approach the counterclock parameter is set to false the startangle parameter the starting angle has also been moved deg using the startangle parameter so that the first segment starts at the top of the chart expanding segments it can be useful to emphasis particular segment of the pie chart by exploding itthat is separating it out from the rest of the pie chart this can be done using the explode parameter of the pie(function that takes sequence of values indicating how much segment should be exploded by the visual impact of the pie chart can also be enhanced in this case by adding shadow to the segments using the named shadow boolean parameter the effect of these are shown below