import re
 
class Ray(object):
    def __init__(self, position, direction):
        self.position = position
        self.direction = direction
 
    def __getattr__(self, name):
        pat = re.compile('^(\w+)_is_zero$')
        if pat.match(name):
            prop = pat.findall(name)[0]
            if prop == 'position':
                return self.position[0] == 0 and self.position[1] == 0
            elif prop == 'direction':
                return self.direction[0] == 0 and self.direction[1] == 0
 
        raise AttributeError
 
ray = Ray([0, 0], [1, 1])
print ray.position
print ray.direction
print ray.position_is_zero
print ray.direction_is_zero