How to pass on argparse argument to function as kwargs?

问题

I have a class defined as follows

class M(object):
    def __init__(self, **kwargs):
        ...do_something

and I have the result of argparse.parse_args(), for example:

> args = parse_args()
> print args
Namespace(value=5, message='test', message_type='email', extra="blah", param="whatever")

I want to pass on the values of this namespace (except message_type) to create an instance of the class M. I have tried

M(args)

but got an error

TypeError: __init__() takes exactly 1 argument (2 given)

which I do not understand. How can I

1. remove the value message_type from the list in args
2. pass on the values as if I would type M(value=5, message='test', extra="blah", param="whatever") directly.

回答1:

You need to pass in the result of vars(args) instead:

M(**vars(args))

The vars() function returns the namespace of the Namespace instance (its __dict__ attribute) as a dictionary.

Inside M.__init__(), simply ignore the message_type key.

来源：https://stackoverflow.com/questions/15206010/how-to-pass-on-argparse-argument-to-function-as-kwargs