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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 fixchars(self, text):
 """Find and replace problematic characters."""

        keys = ''.join(Config.CHARFIXES.keys())
        values = ''.join(Config.CHARFIXES.values())
        fixed = text.translate(str.maketrans(keys, values))
        if fixed != text:
            self.modified = True
        return fixed