code: def _ps_extract_pid(self, line):
          
          this_pid = self.regex['pid'].sub(r'\g<1>', line)
          this_parent = self.regex['parent'].sub(r'\g<1>', line)
          
          # Return the main / parent PIDs
          return this_pid, this_parent
docs: Extract PID and parent PID from an output line from the PS command