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.
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Question: wyfKgihlkYvlIOXsZWHlnOuaYJSnmW

Answer: wyfKgihlkYvIOXsZWHnuaJSm


Question: PyZbsZSaDcLOZOMDqVfMKRMllF

Answer: PyZbsSaDcLOMqVfKRlF


Question: NOXIdIppfrgUFWCgdPvNqsZOjPxB

Answer:
NOXIdpfrgUFWCPvqsZjxB