I want to build a query for sunburnt (solr interface) using class inheritance and therefore adding key-value pairs together. The sunburnt interface takes keyword arguments. How can I transform a dict ({'type':'Event'}) into keyword arguments (type='Event')?
See also: What do ** (double star/asterisk) and * (star/asterisk) mean in a function call? - the corresponding question for people who encounter the syntax and are confused by it.
Use the double-star (aka double-splat?) operator:
func(**{'type':'Event'})
is equivalent to
func(type='Event')
func(**myDict) .i.e myDict = {"type": "event"}
Commented
Apr 19, 2011 at 0:57
** operator would be helpful here.
** operator will unpack the dict elements and thus **{'type':'Event'} would be treated as type='Event'
func(**{'type':'Event'}) is same as func(type='Event') i.e the dict elements would be converted to the keyword arguments.
FYI
* will unpack the list elements and they would be treated as positional arguments.
func(*['one', 'two']) is same as func('one', 'two')
Here is a complete example showing how to use the ** operator to pass values from a dictionary as keyword arguments.
>>> def f(x=2):
... print(x)
...
>>> new_x = {'x': 4}
>>> f() # default value x=2
2
>>> f(x=3) # explicit value x=3
3
>>> f(**new_x) # dictionary value x=4
4
