Introducing and，introducingand,print 'a' an

Introducing and，introducingand,print 'a' an

print 'a' and 'b'print '' and 'b' print 'a' and 'b' and 'c'# 0, '', [], (), {}, and None are false in a boolean context; # everything else is true. #instances of classes are true in a boolean context, #If all values are true in a boolean context, #and returns the last value. #In this case, and evaluates 'a', which is true, then 'b', which is true, #and returns 'b'.#If any value is false in a boolean context, and returns the first false value. #In this case, '' is the first false value.#All values are true, so and returns the last value, 'c'.