'Retrieve the total size of the resource at the given path.
This method may be overridden by subclasses.
.. versionadded:: 3.1
.. versionchanged:: 4.0
This method is now always called, instead of only when
partial results are requested.'

def get_content_size(self):

    stat_result = self._stat()
    return stat_result[stat.ST_SIZE]
