from the top of my head: - def bad_default(x = []) - bool('False') - 1--1 #typo - x = 42; y = 42L ; x==y,hex(x)==hex(y) - type(5/2) # <class 'float'>

from the top of my head: - def bad_default(x = []) - bool('False') - 1--1 #typo - x = 42; y = 42L ; x==y,hex(x)==hex(y) - type(5/2) # <class 'float'> or <type 'int'> (python2 versus python3)