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.

Q: SwUTgAzgSuHxHiuLjUMlBpkqrU

A: SwUTgAzuHxiLjMlBpkqr
****
Q: UDpEypcSPamksrQnESqdDAN

A: UDpEycSPamksrQnqdAN
****
Q: JHcpuDNsiGAmslNCHIcxuuCOJu

A:
JHcpuDNsiGAmlCIxO
****