explorer.py 文件源码

def install(self, methodIdentifier):
        """Install myself on my instance in place of this method.
        """
        oldMethod = getattr(self.instance, methodIdentifier, None)

        # XXX: this conditional probably isn't effective.
        if oldMethod is not self:
            # avoid triggering __setattr__
            self.instance.__dict__[methodIdentifier] = (
                new.instancemethod(self, self.instance,
                                   self.instance.__class__))
            self.oldMethod = (methodIdentifier, oldMethod)