code: def allFileExists(fileList):
      
      allExists = True
      for fileName in fileList:
          allExists = allExists and os.path.isfile(fileName)
      return allExists
docs: Check that all file exists.
  
      :param fileList: the list of file to check.
  
      :type fileList: list
  
      Check if all the files in ``fileList`` exists.