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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 prefix_keys(self, prefix, strip_prefix=False):
 """Get all keys that begin with ``prefix``. :param prefix: Lexical prefix for keys to search. :type prefix: bytes :param strip_prefix: True to strip the prefix from yielded items. :type strip_prefix: bool :yields: All keys in the store that begin with ``prefix``. """

        keys = self.keys(key_from=prefix)

        start = 0
        if strip_prefix:
            start = len(prefix)

        for key in keys:
            if not key.startswith(prefix):
                break
            yield key[start:]