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.

Example Input: hwuafkzTfllMQgESKLgjUY
Example Output: hwuafkzTlMQgESKLjUY

Example Input: XjRLBIuGSzGcqVUCMPmbiFBnjKR
Example Output: XjRLBIuGSzcqVUCMPmbiFnK

Example Input: vqjyphcluSVsBtlQGXUvzwFBa
Example Output:
vqjyphcluSVsBtQGXUzwFa