docs: def addFilename( self, filename ):
          """
          Adds a new filename to the top of the list.  If the filename is \
          already loaded, it will be moved to the front of the list.
          
          :param          filename | <str>
          """
          filename = os.path.normpath(nativestring(filename))
          
          if filename in self._filenames:
              self._filenames.remove(filename)
          
          self._filenames.insert(0, filename)
          self._filenames = self._filenames[:self.maximumLength()]
          
          self.refresh()