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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 _unescape_match(self, match):
 """Given an re.Match, unescape the escape code it represents."""

        char = match.group(1)
        if char in self.ESCAPE_LOOKUP:
            return self.ESCAPE_LOOKUP[char]
        elif not char:
            raise KatcpSyntaxError("Escape slash at end of argument.")
        else:
            raise KatcpSyntaxError("Invalid escape character %r." % (char,))