docs: def new(self, filename=None):
          """start a session an independent process"""
          path = (self.exec_path,)
          if self.exec_path.filetype() in ('py', 'pyw', 'pyz', self.FTYPE):
              # get the absolute path to the python-executable
              p = find_executable("python")
              path = (p, 'python') + path
          else:
              # if run in frozen env (.exe):
              # first arg if execpath of the next session:
              path += (self.exec_path,)
          if filename:
              path += ('-o', filename)
          os.spawnl(os.P_NOWAIT, *path)