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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 iterkeys(self):
 """Unsorted iterator over keys"""

        patterns = self.patterns
        replace = self.replace
        seen = set()
        for key in six.iterkeys(self.base):
            for pattern in patterns:
                m = pattern.match(key)
                if m:
                    ret = m.group('key') if replace else m.group()
                    if ret not in seen:
                        seen.add(ret)
                        yield ret
                    break
        for key in DictMethods.iterkeys(self):
            if key not in seen:
                yield key