[rules-users] Retrieve values from a Map

[Manav]

I am new to drools and currently using version 5.1 for my testing. 

I am facing an issue with retrieving a value from Map if a key is present 

In my drl if i do this 

$c : Client (language contains "Japanese" , lang : language -> 
(language.get("Japanese").equals("Expert")))

it works ...but if i want to retrieve the value of the key i am not sure how to 
go about it . I tried various approaches but none of them worked 


i would like to do something like 

$c : Client (language contains "Japanese", $langValue : 
language.get("Japanese")) 


Can some one please guide me how to go about it . 

Regards,
Manav