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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 delete(self, key, noreply=None):
 """ The memcached "delete" command. Args: key: str, see class docs for details. noreply: optional bool, True to not wait for the reply (defaults to self.default_noreply). Returns: If noreply is True, always returns True. Otherwise returns True if the key was deleted, and False if it wasn't found. """

        if noreply is None:
            noreply = self.default_noreply
        cmd = b'delete ' + self.check_key(key)
        if noreply:
            cmd += b' noreply'
        cmd += b'\r\n'
        results = self._misc_cmd([cmd], b'delete', noreply)
        if noreply:
            return True
        return results[0] == b'DELETED'