docs: async def start(self):
          """Start process execution."""
          # Workaround for pylint issue #1469
          # (https://github.com/PyCQA/pylint/issues/1469).
          self.proc = await subprocess.create_subprocess_exec(  # pylint: disable=no-member
              *shlex.split(self.command),
              stdin=subprocess.PIPE, stdout=subprocess.PIPE,
              stderr=subprocess.STDOUT
          )
  
          self.stdout = self.proc.stdout
  
          return self.proc.pid