django:dispatch and handler

def dispatch(self, request, *args, **kwargs):
    # Try to dispatch to the right method; if a method doesn't exist,
    # defer to the error handler. Also defer to the error handler if the
    # request method isn't on the approved list.
    if request.method.lower() in self.http_method_names:
        handler = getattr(self, request.method.lower(), self.http_method_not_allowed)
    else:
        handler = self.http_method_not_allowed
    return handler(request, *args, **kwargs)

一个getattr的例子

class person():
    name = "Zhang"
    age = 18
t = test()
print(getattr(t, "name", "There is no such property"))      　　　　     

handler = getattr(self, request.method.lower(), self.http_method_not_allowed) 的结果是得到一个request.method， 例如post，get等等。
而return handler(request, *args, **kwargs)将参数(request, *args, **kwargs)输入request.method。