'Add a new tab stop at *position*, a |Length| object specifying the
location of the tab stop relative to the paragraph edge. A negative
*position* value is valid and appears in hanging indentation. Tab
alignment defaults to left, but may be specified by passing a member
of the :ref:`WdTabAlignment` enumeration as *alignment*. An optional
leader character can be specified by passing a member of the
:ref:`WdTabLeader` enumeration as *leader*.'

def add_tab_stop(self, position, alignment=WD_TAB_ALIGNMENT.LEFT, leader=WD_TAB_LEADER.SPACES):

    tabs = self._pPr.get_or_add_tabs()
    tab = tabs.insert_tab_in_order(position, alignment, leader)
    return TabStop(tab)
