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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 free(self):
 """Remove the lock on the connection if the connection is not active :raises: ConnectionBusyError """

        LOGGER.debug('Connection %s freeing', self.id)
        if self.handle.isexecuting():
            raise ConnectionBusyError(self)
        with self._lock:
            self.used_by = None
        LOGGER.debug('Connection %s freed', self.id)