In this task, you are given a string of characters. You need to remove duplicate characters from the string if any, and return the resulting string.

Ex Input:
CHIKoErswWcbipbgjjmyU

Ex Output:
CHIKoErswWcbipgjmyU


Ex Input:
vSdLBugCbKUwEzgkOnVZvyGCRdrwlq

Ex Output:
vSdLBugCbKUwEzkOnVZyGRrlq


Ex Input:
huZGjSZbzraOBIBjsbJmLZ

Ex Output:

huZGjSbzraOBIsJmL


