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]: XttLMRTVbiQDKPMEXyeXPSoDGCehY
[A]: XtLMRTVbiQDKPEyeSoGChY


[Q]: EpmhbcqBTOnKFvPKTORfDMqS
[A]: EpmhbcqBTOnKFvPRfDMS


[Q]: PLjJDIORjmnkxLEVzasB
[A]:
PLjJDIORmnkxEVzasB