'Go to the section/subsection in the courseware.
Every section must have at least one subsection, so specify both the
section and subsection indices.
Arguments:
section_index: A 0-based index of the section to navigate to.
subsection_index: A 0-based index of the subsection to navigate to.'

def go_to_section_by_index(self, section_index, subsection_index):

    try:
        section_title = self._section_titles()[section_index]
    except IndexError:
        raise ValueError("Section    index    '{0}'    is    out    of    range.".format(section_index))
    try:
        subsection_title = self._subsection_titles((section_index + 1))[subsection_index]
    except IndexError:
        raise ValueError("Subsection    index    '{0}'    in    section    index    '{1}'    is    out    of    range.".format(subsection_index, section_index))
    self.go_to_section(section_title, subsection_title)
