parameters: (self)
docstring: Create an empty file if necessary.
  
      This method will not initialize the file. Instead it implements a
      simple version of "touch" to ensure the file has been created.
docstring_summary: Create an empty file if necessary.
docstring_tokens: Create an empty file if necessary .
function: def _create_file_if_needed(self):
      """Create an empty file if necessary.
  
      This method will not initialize the file. Instead it implements a
      simple version of "touch" to ensure the file has been created.
      """
      if not os.path.exists(self._filename):
        old_umask = os.umask(0177)
        try:
          open(self._filename, 'a+b').close()
        finally:
          os.umask(old_umask)
function_tokens: def _create_file_if_needed ( self ) : if not os . path . exists ( self . _filename ) : old_umask = os . umask ( 0177 ) try : open ( self . _filename , 'a+b' ) . close ( ) finally : os . umask ( old_umask )