To reverse the key-value of a dict

inv_map = {v: k for k, v in map.items()} You can write it as.

The code description is In fork, vin map.items(), k and v receive key and value, respectively Code to save the key-value of {v:k} back in inverted dict format.

dict((v, k) for k, v in map.iteritems()) It has to be written as.

I'll explain the code here, too In fork, vin map.items(), k and v receive key and value, respectively After the key-value of (v,k) is temporarily stored as an inverted generator, The generator is converted back to dict at dict().