<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_tool_definition(self, target):
 """ Returns tool specific dic or None if it does not exist for defined tool """

        if target not in self.targets_mcu_list:
            logging.debug("Target not found in definitions")
            return None
        mcu_record = self.targets.get_mcu_record(target) if self.mcus.get_mcu_record(target) is None else self.mcus.get_mcu_record(target)
        try:
            return mcu_record['tool_specific'][self.tool]
        except KeyError:
            return None