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: osRkjysAYNKHZYSWIEORxnZJWf

A: osRkjyAYNKHZSWIEOxnJf
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Q: wKewCMTAYgicAyjnUQXzhjthHFCe

A: wKeCMTAYgicyjnUQXzhtHF
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Q: OWsvUKqZcWjNqJfyhgJkVKMgydE

A:
OWsvUKqZcjNJfyhgkVMdE
****