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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 scan_keys(self, count=None):
 """Iter on all the key related to the current instance fields, using redis SCAN command Parameters count: int, default to None (redis uses 10) Hint for redis about the number of expected result Yields ------- str All keys found by the scan, one by one. A key can be returned multiple times, it's related to the way the SCAN command works in redis. """


        pattern = self.make_key(
            self._name,
            self.pk.get(),
            '*'
        )

        return self.database.scan_keys(pattern, count)