class Mutant(object):
    """A mutant!"""

def __init__(self):
    """A mutant is born with only 1 eye and 1 mouth"""
self.eyes = 1
self.mouth = 1
self.location = 'Montana'

def roll_to(self, location):
    """If they have limbs, running is less dangerous"""
if hasattr(self, 'limbs'):
    print('Your mutant broke its limbs off!!')
del self.limbs
self.location = location

def run_to(self, location):
    """If they don't have limbs, running is not effective"""
if not hasattr(self, 'limbs'):
    print('Your mutant tries to run but he has no limbs.')
else:
    self.location = location

def grow_limbs(self, number_of_limbs):
    """Ah, evolution!"""
assert number_of_limbs > 0, 'Cannot grow 0 or less limbs...'
if hasattr(self, 'limbs'):
    self.limbs += number_of_limbs
else:
    self.limbs = number_of_limbs
Python — следует ли инициализировать все переменные-члены в __init__