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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 search(self, pattern, count=None):
 """ Search the keys of the given hash using the specified pattern. :param str pattern: Pattern used to match keys. :param int count: Limit number of results returned. :returns: An iterator yielding matching key/value pairs. """

        return self._scan(match=pattern, count=count)