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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 getExistingFile(name, max_suffix=1000):
 """Add filename suffix until file exists @return: filename if file is found @raise: ValueError if maximum suffix number is reached while searching """

    num = 1
    stem, ext = os.path.splitext(name)
    filename = name
    while not os.path.exists(filename):
        suffix = "-%d" % num
        filename = stem + suffix + ext
        num += 1
        if num >= max_suffix:
            raise ValueError("No file %r found" % name)
    return filename