'Add content on studio course page under specified section'

def _studio_add_content(self, section_index):

    self._auto_auth(self.STAFF_USERNAME, self.STAFF_EMAIL, True)
    self.studio_course_outline.visit()
    subsection = self.studio_course_outline.section_at(section_index).subsection_at(0)
    subsection.expand_subsection()
    subsection.add_unit()
    unit_page = ContainerPage(self.browser, None)
    unit_page.wait_for_page()
    add_html_component(unit_page, 0)
    unit_page.wait_for_element_presence('.edit-button', 'Edit    button    is    visible')
    click_css(unit_page, '.edit-button', 0, require_notification=False)
    unit_page.wait_for_element_visibility('.modal-editor', 'Modal    editor    is    visible')
    type_in_codemirror(unit_page, 0, self.HTML_CONTENT)
    click_css(unit_page, '.action-save', 0)
