code: def __clear_variable_watch(self, tid, address):
          
          if self.has_hardware_breakpoint(tid, address):
              self.erase_hardware_breakpoint(tid, address)
docs: Used by L{dont_watch_variable} and L{dont_stalk_variable}.
  
          @type  tid: int
          @param tid: Thread global ID.
  
          @type  address: int
          @param address: Memory address of variable to stop watching.