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: UDpEypcSPamksrQnESqdDAN

A: UDpEycSPamksrQnqdAN
****
Q: vbzTYPGtcLOutwmpcLPOyjppQI

A: vbzTYPGtcLOuwmpyjQI
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Q: ktWYQIoDdqxfApnOvFWSAhj

A:
ktWYQIoDdqxfApnOvFShj
****