Why setter and deleter still work when use only read in Python 2.7

Question

I use read only in Python but I setter and deleter still work. This code

class Character():
    def __init__(self, name):
        self._name = name
    def getname(self):
        return self._name
    name = property(fget=getname, fset=None, fdel=None, doc=None)

c = Character('c')

c._name #Output 'c'

c.name #Output 'c'

c.name = 'd'

del c.name

_name is private attribute, why I still use c._name

In property for getter but setter and deleter still work.