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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 unindent(self, lines):
 """Removes any indentation that is common to all of the given lines."""

        indent = min(
            len(self.re.match(r'^ *', line).group()) for line in lines)
        return [line[indent:].rstrip() for line in lines]