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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def create_unique_id(prefix, existing_ids):
 """Return a unique string ID from the prefix. First check if the prefix is itself a unique ID in the set-like parameter existing_ids. If not, try integers in ascending order appended to the prefix until a unique ID is found. """

    if prefix in existing_ids:
        suffix = 1
        while True:
            new_id = '{}_{}'.format(prefix, suffix)
            if new_id not in existing_ids:
                return new_id
            suffix += 1

    return prefix