'Update the progress with a percentage, including updating the progressbar as well as calling the progress
callback.
:param float percentage: Percentage of the progressbar. from 0.0 to 100.0.
:return: None'

def _update_progress(self, percentage):

    if self._show_progressbar:
        if (self._progressbar is None):
            self._initialize_progressbar()
        self._progressbar.update((percentage * 10000))
    if (self._progress_callback is not None):
        self._progress_callback(percentage)
