inheritance

[Sean Ross]

For example:

class Base:
    def __init__(self, value):
        self.value = value
    def __mul__(self, other):
        return self.__class__(self.value * other.value)

class Child(Base):
    def __init__(self, value):
        Base.__init__(self, value)

x = Base(2)
y = Base(3)
z = Child(4)
w = Child(5)
print x*y
print z*w

"""OUTPUT
<__main__.Base instance at 0x009991E0>
<__main__.Child instance at 0x009991E0>
"""