code: def is_executable(exe_name):
      
  
      if not isinstance(exe_name, str):
  
          raise TypeError('Executable name must be a string.')
  
      def is_exe(fpath):
  
          return os.path.isfile(fpath) and os.access(fpath, os.X_OK)
  
      fpath, fname = os.path.split(exe_name)
  
      if not fpath:
  
          res = any([is_exe(os.path.join(path, exe_name)) for path in
                     os.environ["PATH"].split(os.pathsep)])
  
      else:
  
          res = is_exe(exe_name)
  
      if not res:
          raise IOError('{} does not appear to be a valid executable on this '
                        'system.'.format(exe_name))
docs: Check if Input is Executable
  
      This methid checks if the input executable exists.
  
      Parameters
      ----------
      exe_name : str
          Executable name
  
      Returns
      -------
      Bool result of test
  
      Raises
      ------
      TypeError
          For invalid input type