Long Methods are methods that span too many lines. When a method gets too long, perhaps it is responsible for more tasks than it should be.
def long_method(self): # Do first thing # Do second thing # Do third thing # Do fourth thing
Books about code smells
Learn to write better smelling code.
Refactoring: Improving the Design of Existing Code
Code smells: A Predictor of Remarkable Quality Improvement
Clean Code: A Handbook of Agile Software Craftsmanship