Import and replace existing ASM Policy (Security policy)

Using GUI, i'm able to Security->Application Security->Security Policies->Import 1. Choose file 2. I select to replace an existing policy and Import.

 

How can i do this via api. I do not get option to replace an existing ASM Policy. I tried all options like upload_policy, import_policy and export_policy which does not give me an option to replace an existing one.