The DRY or “Don’t Repeat Yourself” principle is a software development practice aimed at reducing repetition of information. In this lesson, you learned how to apply DRY when making comparisons in your Python code.
This code sample from the lesson illustrates how to apply DRY:
name = 'Mahdi'
people_i_like = ['Mahdi', 'John', 'Linda']
if name in people_i_like:
print 'yay!'