What is cyclomatic complexity or McCabe's complexity?
It refers to the number of times a line of source code is entered in its execution.
|Number of executions||Level of complexity|
|1 to 10||Not complex|
|11 to 20||Moderately complex|
|21 to 50||Really complex|
|More than 50||Too complex|
It is advisable to endeavor to keep the cyclomatic complexity as low as possible (according to this external site); you may want to refactor code beyond a certain threshold. The chart was adapted/taken from pages 474 and 475 of Expert Python Programming.