code: def hook(self, debug, pid, address):
          
          return debug.break_at(pid, address, self)
docs: Installs the function hook at a given process and address.
  
          @see: L{unhook}
  
          @warning: Do not call from an function hook callback.
  
          @type  debug: L{Debug}
          @param debug: Debug object.
  
          @type  pid: int
          @param pid: Process ID.
  
          @type  address: int
          @param address: Function address.