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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 parse_format_index(self, text):
 """Parse format index."""


        base = 10
        prefix = text[1:3] if text[0] == "-" else text[:2]
        if prefix[0:1] == "0":
            char = prefix[-1]
            if char == "b":
                base = 2
            elif char == "o":
                base = 8
            elif char == "x":
                base = 16
        try:
            text = int(text, base)
        except Exception:
            pass
        return text