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]: ngGDcYbncvLyDvYspBnpiSDhWKg
[A]: ngGDcYbvLyspBiShWK


[Q]: eSfCVZsCDnsQYKZLJZknwVEUHre
[A]: eSfCVZsDnQYKLJkwEUHr


[Q]: pKZWKxZqQdaAHUrMTJMYiZhu
[A]:
pKZWxqQdaAHUrMTJYihu